Environmental Microbiology Lab Report

Environmental Microbiology Lab Report
Collection, Observation, and Analysis of Microorganisms in the human environment Introduction
The necessity and value of collecting, identifying, and analyzing the various microbes regularly
encountered in the daily human environment becomes quite apparent when one gains even a very
basic knowledge of how diseases are acquired and spread. The purpose of this lab was to collect and
observe microbes from environmental and human body samples by culturing them on the
appropriate media using aseptic transfer techniques. ... Show more content on Helpwriting.net ...
V. Making heat fixed bacterial smears of all the samples: 1. Take the twelve sterile glass slides and
label their corners using the wax pencil. Since a sample from two different colonies is going to be
taken from each of the six tested locations, label them accordingly: E1C1 (environmental sample
number one, colony number one), E1C2, E2C1, E2C2, E3C1, E3C2, E4C1, E4C2, NC1, NC2, TC1,
TC2. 2. Place a drop of distilled water on the center of each slide.
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb bbbbbbbbbbb incubator.
Observe the intensity of growth and the number of colonies formed from each sample. Write these
results on a piece of paper. 4. Take out the Bunsen burner and connect it to the available gas source
using the plastic tubing. Turn the gas on. 5. Use the igniter to ignite the Bunsen burner flame. 6.
With one hand, take the inoculating loop and pass it through the flame until it is red– 7. With the
other hand, open one of the Petri dishes slightly. 8. Take the sterilized
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Microbiology: Unknown Discussion
Christine Espinoza
Professor Rojas
Microbiology 200
13 December 2015
Unknown Discussion After many performed test such as the API 20E test strip, motility test,
inoculated plates, gram stain, an identification flow chart which began with the results from an
indole, MR, VP, and citrate test. This amongst many other test. These results brought the conclusion
of my unknown culture to be Escherichia coli, my unknown number was 11. Escherichia coli also
for short E.coli, is a rod–shaped, gram–negative bacteria, this bacteria is usually motile and grows
best at 37℃, because this is the temperature of the human body where it is normally found, because
it is a bacteria that can be found in our normal flora it is a bacteria that is needed in our

Unknown Bacteria: Microbiology Lab Report
UNKNOW BACTERIA LAB REPORT
UNKNOWN 36
Introduction
The purpose of this lab was to identify two unknown bacteria from a mixed culture. The reason for
identification of unknown bacteria was to help students recognize different bacteria through
different biochemical tests and characteristics. This is important in the medical field because
identification of unknown bacteria can help treat a patient by knowing the contributing source of a
disease. Also knowledge of different bacteria helped others make antibiotics used today. This lab
was completed by using the methods learned thus far in identification of bacteria.
Materials and Methods
A mixed culture of two unknown bacteria was provided by the instructor. The methods used for ...
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The colonies were smooth, translucent, and had a white brownish color. The Gram stain resulted in
Gram positive cocci. After the Gram stain was completed, the bacteria were streaked on a Mannitol–
Salt Agar plate and a Catalase test was performed. After these test were completed a Phenol Red
Dextrose Fermentation tube was inoculated, and a SIM Tube inoculated.
The Unknown Bacteria 36/Bacteria # 2 on a TSA plate was examined by the naked eye and under a
dissecting microscope. Bacteria # 2 was approximately 3 – 4 mm in diameter. They were circular in
form with an entire margin and a flat elevation. The colonies were rough (granular), translucent, and
white brownish color with black granules. The Gram stain resulted in a Gram negative rod. After the
Gram stain was completed, the bacteria were streaked on an Eosin –Methylene Blue Agar plate and
an Enterotube II was inoculated.
See Table 1 and Flow Chart 1 for results of Bacteria # 1 and Table 2 and Flow Chart 2 for results of
Bacteria # 2.
Table 1: Biochemical Test Results (Bacteria # 1) TEST | PURPOSE | REAGENTS |
OBSERVATIONS | RESULTS | Gram Stain | To determine the Gram reaction of Bacteria #1 |
Crystal violet, Iodine, Alcohol, Safranin | Purple cocci | Gram positive cocci | MSAAgar plate | To
determine Gram positive Staphylococcus species | None | Yellow halo around streak |

The Occupational Characteristics of Microbiology
Graduating from The University at Albany's Biology program provides a wide selection of job
opportunities upon leaving college. While students have the option of picking from a B.A. or a B.S.,
the focus of a B.S. in biology has more scientific purposes. Graduation requirements are difficult,
but certainly not impossible, requiring 67–68 credits over 4 years. These credits include 36 biology
credits, 16 chemistry credits, 8 math credits and 8 physics credits. The job opportunities that become
open to the holder of a B.S. range across many fields, including education, health and medicine, and
a plethora of research opportunities. Just some of the many opportunities open to biology grads
include laboratory technicians, researchers, pharmacists, teachers, doctors, and microbiologists. The
opportunities change as a biology major may decide to master in a more specific science of biology,
and microbiology is one popular field to enter. According to Encyclopedia Britannica, a
microbiologist is someone who studies "microorganisms, or microbes, a diverse group of minute,
simple life forms that include bacteria, archaea, algae, fungi, protozoa and viruses" (Pg. 1). On a day
to day basis, an average microbiologist will deal with treating infections; identifying and classifying
new organisms as they are discovered; and finding new uses for already discovered organisms.
Other various tasks a microbiologist may perform are epidemiology, writing research reports and
describing new

Microbiology Personal Statement
I have chosen to pursue a major in microbiology due to my high interest in public and international
health. I am interested in how microbes play a role in the functionality of the human body.
Moreover, I find the ecological roles of microbes to be critical to our understanding of other fields
of science that impact human health. The niches of microbes throughout a variety of environments
indicates the human impact on our ecosystem.
Service has been important in my life which has inspired me to pursue a minor in non–profit
leadership. I witnessed firsthand how non–profits can positively influence the health of others
through working within the pharmacy of Urban Ministries to provide medications for
underprivileged citizens, leading simulating activities within Pruitt Health to increase the quality of
treatment of the elderly, and providing nutritious meals within Clemson Community Care and a
locally based organization called With Love from Jesus. The major issues concerning the non–profit
sector include sustainability and the gathering of resources. I have viewed these issues through
integrating science and service by assisting with teaching laboratory bench techniques to high–
school ... Show more content on Helpwriting.net ...
subtilis has shaped my certainty in my microbiology related field of study. My participation in
Alternative Spring Break trips focused on the importance of physical and mental health education
within women and children in crisis has shaped my certainty in my field of study. Microbiology is
broad, providing many applications for its use in the treatment of mental illness. Studies have shown
that the interaction between the gut microbiota and the brain could be a factor in the obtaining of
mentally related diseases. There are broad applications of microbiology. This field is always
evolving, which allows a wide variety of

Microbiology Lab Report
Microbiology involves the study of microbes and their relevant scientific roles. The purpose of this
lab report is to use the methods and techniques acquired from the microbiology course to identify an
unknown bacterium. The assigned culture for this report is Unknown 28. Various laboratory
techniques were performed in this process in order to draw conclusions as to what microorganism
the unknown sample may contain.
Before proper tests can be performed, the most important aspect to laboratory procedures are aseptic
techniques. These techniques are crucial to ensure that no contamination occurs during the culturing
process (1). Although the exact steps may vary depending on the media and type of transfer, the
main components of the aseptic techniques ... Show more content on Helpwriting.net ...
Controls are especially important when it comes to identifying unknown microbes as it is done
within this report. Positive controls serve as a comparison or model of how the performed test
should react if the microbe tested is positive. This enables the experimenter to compare results and
determine if their culture is positive or negative for the reactions. In contrast, the negative controls
serve to model what the test should look like if nothing is done or if the organism tested is negative.
For every laboratory exercise performed in this course, there are positive and negative control
demonstrations available for students to reference. These are very useful in aiding students when
they are determining the result of their unknown culture

Various test performed to identify two bacterium that were unknown, one was plaque that were
scrapped from the teeth and the second was an unknown given. It resulted that the unknown
bacterium is Staphylococcus epidermidis. Staphylococcus epidermidis has three drug resistance, and
no secondary metabolites. The plaque scrapped from the teeth had a morphology of bacilli and is
gram positive. Staphylococcus is gram positive, it is catalase positive and oxidase negative. The
minimal inhibition concentration of Ethanol extract is 0.001 micro liters for S. epidermidis. The
minimal inhibition concentration for the plaque was at a concentration 0.1 ml of ethanol extract and
a concentration of 0.01 ml for distilled water.
Background:
Staphylococcus ... Show more content on Helpwriting.net ...
Oxidase Test: Using a sterilized loop inoculate a loopful of bacteria into the test square and observe
for any change in color. If it turns blue it is oxidase positive, and if it remains the same color then it
is oxidase negative.
Streaking: Using the method of quadrant streak a loopful of bacteria onto one side of the BHI agar
plate and sterilize your loop. Then using the sterilized loop, grab one end of the side where it was
previously streaked and slide it across on another side of the agar plate. Then using the sterilized
loop grab the one end of that same side where it was previously streaked and slide it to the other
corner of the agar plate. Sterilized your loop again using the flame and grab the last end of the
previously streaked and streak the last corner of the agar plate. This should have four corners the
fourth corner being the most diluent will have the most isolated colony forming.
Dilution series: Use microcentrifuge tubes for the dilutions, if the final dilution is 10x^4 , you will
need 5 microcentrifuge. Label the one as the stock, 10X, 10X^2, 10X^3 and 10X^4, then add 1 ml
of the diluent X. Add .9 ml of the diluent to each concentration microcentrifuge and
0.1 ml of the substance that will be diluted on to the first microcentrifuge which is the one labeled as
10X, using the micropipette. Then add 0.1 ml of from the 10X microcentrifuge onto the 10X^2
microcentrifuge and so on until you reach

Microbiology Pioneers
Contributors to Microbiology
Pioneers of Microbiology I. Antonie van Leeuwenhoek (Oct. 24, 1632– Aug. 30, 1723) A. In 1676
Leeuwenhoek saw tiny organisms in water, he was the first man to observe and describe bacteria
accurately. He discovered microscopic nematodes, blood cells and sperm. He also made over 500
microscopes to view specific objects. B. Microbiology is concerned with the study of all forms of
life that are too small to be seen with the naked eye. Antonie's work dealt with bacteria, which are
tiny microorganisms that can only be seen with the help of instruments like the microscope, which
he invented. II. John Tyndall (Aug. 2, 1820– Dec. 4, 1893) C. In 1877 Tyndall demonstrated that
dust ... Show more content on Helpwriting.net ...
IX. Matthias Schleiden (1804 – 1881) Q. Matthias was the first to recognize the importance of cells
as fundamental units of life. He stated that all plants are made of cells, which eventually help lead to
the creation of the cell theory. R. In 1838,he argued that all the various plants structures are
composed of cells or their derivatives (phytogenesis). X. Joseph Lister (1827 – 1912) S. In 1865
lister concluded that sepsis was akin to fermentation and was initiated by infectious agents, air–born.
In 1867 he shown that antiseptic procedures are very successful T. This discovering made it easier
for surgeons when performing an operations and prevents the patients from getting infected. This
operation marked a turning point in the acceptance of germ theory and antisepsis among physicians.
XI. Ernst Heinrich Philipp August Haeckel (Feb. 16, 1834 – Aug. 9, 1919) U. Ernst Haeckel
discovered, described and named thousands of new species, mapped an ancestral tree relating all life
forms, and coined many terms in biology including: anthropogeny, ecology, phylum, phylogeny,
stem cell, and the kingdom Protista. V. Haeckel promoted and popularized Charles Darwin 's work
in Germany and developed the controversial recapitulation theory claiming that an individual
organism 's biological development parallels and summarizes its species '

Microbiology Case Study 1
Introduction to Microbiology – Case Study 1
Kristen Alejos
You are working as an emergency room nurse in Topeka when a mother brings in her 8 year old son
because of severe, bloody diarrhea. When questioned, the boy said that it hurts when he goes to the
bathroom and his mother said he had vomited in the previous two days. When asked about their
previous movements, the mother and son both mentioned a backyard barbeque that had taken place
6 days earlier. The boy complained that his mother made him eat a "pink" hamburger that was not
thoroughly cooked. A physical examination of the boy revealed nothing out of the ordinary except
dehydration from the diarrhea. Lab tests showed that he had 13,000 white blood cells/microliter of
... Show more content on Helpwriting.net ...
(3 pts) One important virulence factor produced by E. Coli is toxins. Toxins are proteins secreted by
the bacteria that are poisonous to the host. In this case the toxins that are produced by E. Coli,
damage the lining of the small intestine and that is what causes the bloody diarrhea. Sources: –
Leboffie, Michael J. Microbiology. Burton E. Pierce. Morton. Englewood, Co. 2012
3. Based on what you know about the selective and differential capabilities of MacConkey agar,
would it be possible to obtain similar results from a stool sample of a health patient? Why or why
not? (3 pts) The MacConkey agar is capable of growing E. Coli because it inhibits the growth of
Gram–positive bacteria and E. Coli is a gram–negative bacteria. If we took a stool sample from a
healthy patient the selective media would be similar because E. Coli always grows on a MacConkey
agar and E. Coli is always present in the human intestines. However the differential media would
not be similar because of the amounts of E. Coli in the intestines and also whether it is infectious or
not. Different kinds of E. Coli have the ability or inability to ferment lactose which changes the
colors of the dyes after the incubation period. Sources: –Leboffie, Michael J. Microbiology. Burton
E. Pierce. Morton. Englewood, Co. 2012
4. How is this organism spread? How can infection be prevented? (3 pts) According to the Mayo
Clinic Staff, E.Coli is most easily

Microbiology: Microorganisms That Co-exist With Life on...
A diverse collection of microorganisms co–exist with life on Earth; most of them as inhabitants
among plants or oceans, many as normal flora in humans, and some in remote locations in the most
extreme habitats. Despite being ubiquitous in nature and typically harmless, bacteria get particular
attention for causing disease in humans. Correct identification of a microorganism allows for proper
investigation of a particular species, and prevention or treatment of a disease if necessary. During
lab, students were instructed to choose a test tube inoculated with an unknown organism and then
prompted to initiate a series of appropriate lab tests to correctly identify the organism. RESULTS
Unknown 3 was received in Trypticase Soy Broth. A ... Show more content on Helpwriting.net ...
Figure 1. Test Purpose Reagents/Media Observation Results Interpretation Gram Stain Cell wall
composition, morphology Crystal violet, Gram's iodine, Gram's Decolorizer, Safranin Counterstain
Purple circles, clustered in tetrads + Gram positive cocci Methyl Red Detect mixed acid
fermentation MR–VP broth, Methyl Red reagent No change in color – Non–fermenter Urea
hydrolysis Detects enzyme urease Urea broth Yellow color – Does not metabolize urea Figure 2.
Unknown Organism #3 Gram Stain Gram (+) Rod Gram (–) Rod Gram (+) Cocci S. aureus S.
epidermidis E. faecalis M. luteus M. roseus Pigmentation (+) (–) S. aureus S. epididermidis M.
luteus E. faecalis M. roseus Methyl Red (+) (–) S. aureus M. luteus M. roseus Urea Hydrolysis (+)
(–) M. luteus M. roseus Micrococcus roseus DISCUSSION Unknown 3 was identified as
Micrococcus roseus (M. roseus), a gram positive cocci found in soil,

Microbiology begins with Robert Hooke in his discovery of a very important part of biology in the
year of 1665. He observe while looking through a microscope that life existence of small structural
units referred to by Hooke as "little boxes". Hooke constructed his own version of a compound
microscope which had two lenses instead of one. He viewed individual cell like structures through
the lens marking the beginning to "Cell Theory". Hooke microscope lacked the capability of
resolution and it wasn't able to show large cells either. Anton Van Leeuwenhoek discovered live
microorganisms while looking through a magnifying lens through a microscope that was constructed
by him. He describe the microorganisms as "animalcules" that he seen through ... Show more
content on Helpwriting.net ...
Redi gather up some decaying meat in filled two jars full of it. He left one of the jars of meat
unsealed and watched as flies laid eggs on the meat than the eggs developed into larvae. The jar of
meat that had a seal on it contains no maggots because flies couldn't enter into the jar to create any
maggots. This experiment did not prove anything to Redi's antagonists which claimed the
spontaneous generation needed fresh air. Redi composed of another experiment with a jar of
decaying meat that he covered this time around with a net. There still wasn't a sign of maggots even
with air being able to enter into the jar. Although Redi proved his theory, many scientist still
believed that nonliving matter identify by Leeuwenhoek's ''animalcules'' were enough to generate
small organisms. In 1745, an Englishman name John Needham discovered that the existence of
microorganisms were real when he boiled chicken broth and corn broth and then pour them both
into flasks for them to cool off. The results showed that the broths both contain microorganisms that
were developed by the microbes. An Italian scientist Lazzaro Spallanzani suggested 20 years after
Needham discovering proclaiming that Needham may have allowed microorganisms to seep into the
broth from the air after the broth was boiled. Spallanzani

Statement Of Purpose For Microbiology
Statement of Purpose
Name: Ujjwal Rimal
Area of Interest: Microbiology and Immunology.
During his last few months, my grandfather had trouble falling asleep. Frequent cough and his
debilitating health was the matter of concern for our family. The nights had always been horrible as
my father had to take care of him till the dawn. At that time, lung cancer was a fatal disease in
Nepal. His demise gave me an insight into how illness can affect a person's life and of the people
close to him. Intrigued by knowing that a simple microscopic cell with an uncontrolled division took
my dearest one far from me, I began to ponder over the enigma of a microbiological world. As I
grew, my curiosity and inquisitiveness towards diseases began to escalate. Thus, I pursued my
growing interest by opting for Biology as one of the majors in high school.
After completion of Intermediate in Science with biology, I decided to pursue Microbiology as my
major in undergraduate studies at Tri–Chandra Multiple Campus ... Show more content on
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These have forced me to look for other opportunities to continue my education. Department of
Biology at the University of Louisiana at Lafayette has excellent facilities and leading laboratories
in which I can fully realize my scientific interests. I would regard my admission to the University of
Louisiana at Lafayette not only as a great honor but also as a great responsibility and an obligation
to work hard. Furthermore, I chose your country because it is the most developed country in the
world which has the ability to provide all types of education to the domestic as well as the
international student. It has a quality educational institution for better education. Besides these, a lot
of foreign students come to the USA to pursue their higher education, which provides an opportunity
to meet new peoples and share knowledge, experience, as well as a cultural

Antoni Van Leeuwenhoek and His Contribution to...
No one would ever expect a Dutch fabric merchant to be the first to discover some of the most
abundant organisms in the world. Europe was in the midst of a Scientific Revolution as part of the
Renaissance. At this time, new scientific discoveries were being made with the rise of scientists such
as Galileo and Newton. Another prominent name in this revolution was Antoni van Leeuwenhoek.
Leeuwenhoek first worked in a fabric shop in Delft, Holland in the mid–1600s. Leeuwenhoek used
his microscope to observe almost anything he could think of to have a better understanding of what
he was seeing. Antoni van Leeuwenhoek contributed to microbiology because he developed the first
simple microscope, was the first to observe microorganisms, and was ... Show more content on
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"The short (about 1 millimeter) focal lengths of the lenses would have necessitated placing the eye
almost in contact with the lens" ("Anton van Leeuwenhoek"). Leeuwenhoek obtained the clear
image by carefully moving the angle of lighting left and right. Leeuwenhoek's techniques of lighting
samples under the microscope are still not well known today. This was the only secret that he took to
his grave. Even though the simple microscope was difficult to use, scholars visited Leeuwenhoek to
be educated on his design. Leeuwenhoek went all over the world giving demonstrations about his
microscope for high–ranking people. Without Leeuwenhoek's simple microscope, microbiology
today would not be as advanced.
What is even more impressive than configuring a new and improved microscope was the
observations that were seen through the device. First, Leeuwenhoek came up with a theory on the
difference on taste of sugar and salt and examined them each to investigate, why they have their
certain tastes. He was then curious about why pepper had its sharp taste. After inserting the pepper
into snow water, Leeuwenhoek found 3 types of protozoa and a kind of bacteria that was mistaken
as a different animalcule. Robert Hooke, an English natural philosopher, was the first to confirm
Leeuwenhoek's discovery of the microorganisms in the pepper and snow water infusion.

Microbiology Personal Statement
One of my areas of interest is microbiology, particularly the mechanisms by which pathogens evade
host defense systems and cause disease. Since I currently work in a microbiology lab I have read a
few papers dealing with these issues and as such I would like to investigate the clinical aspects of
bacterial infections. Other fields of study that I am interested in are biochemistry and medicinal
chemistry, particularly the synthesis and evaluation of drugs that can potentially treat health
problems. Ever since taking Organic Chemistry the process of drug synthesis has intrigued me. My
professor exposed me to the challenges faced by many scientists in creating synthetic drugs, and I
would be more than happy to get involved with creating novel

Proteus Vulgaris Microbiology
Proteus vulgaris #12
The importance of identification of a certain microorganisms can range between a life threatening
diseases to a creation of certain antibiotic. Understanding the principals of living microbes and
identifying my unknown bacteria through numerous biochemical and metabolism tests, with the
outmost confidence, Proteus vulgaris had the precise qualifications. The point of this report is to
further explore the identification of my unknown bacteria by revealing the results of the experiments
and comparing them to the other six known bacteria: Micrococcus luteus, Staphylococcus aureus,
Staphylococcus epidermidis, Alcaligenes faecalis, Escherichia coli, and Proteus vulgaris that were
used in the lab, as well as comparing and ... Show more content on Helpwriting.net ...
(Harley, 2011, pp. 102–103) Sucrose and lactose serve as a fermentable carbohydrate sources which
promote its growth of fecal forms and provide color change differentiation. (Harley, 2011, p. 104)
Therefore, if E. coli is being platted on the EMB, after plate's incubation period, it should produce a
green metallic sheen on the agar due to the bacteria being a strong fermenter. My unknown bacteria
tested positive for growth, and agar was fermented reddish burgundy in color. Subsequently, the
unknown bacteria was later inoculated with a sterilized loop into the liquid tryptic soy broth and
incubated at an appropriate temperature. Its results were used for proper identification of turbidity,
spots and flocculation. (BD™ Tryptic Soy Broth (TSB), 2008) The results of the unknown were
cloudiness and some settlement on the bottom of the tryptic soy liquid. The next step was conducted
to find out if all the bacteria, as well as the unknown culture, required oxygen for growth, varying
from an aerobic environment, where bacteria needs oxygen to grow, to facultative anaerobic
environment, where bacteria will grow either with or without oxygen but better in its presence. All
the bacteria, along with the unknown, were separately inoculated and tested. My unknown culture
results tested positive for growth in facultative anaerobic environment. In the next sequence of lab
experiments, the results of unknown bacteria were determined by glucose fermentation,

Essay On Microbiology
For this analysis assignment, I used the American Type Culture Collection (ATCC) website to find
technical documents from the microbiology field. I chose two whitepapers written by the same
author but the papers themselves have vastly different purposes. The first white paper informs the
reader of multi–resistant strains and the need for new solutions to this problem. The second
document discuss a new approach to treating multidrug–resistant infections. This memo will explain
the purpose of each document by comparing the intended audience, genre, conventions and the
appeals used. AUDIENCEAs stated above, both documents discuss multidrug–resistant organisms.
Despite their similar topic, each has a different primary audience. The first ... Show more content on
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The second document presents new and relevant findings. Their competitors will look at thus
documents to judge what products they should advertise and where they should be applying their
research. Lastly, both documents must pass the judge, ATCC. In order to be published on the
website, these documents had to be accurate, thorough and relevant. GENREThe documents I chose
were both white papers. A whitepaper purposes a solution or sells information of products as
solutions. Whitepapers typically contain background information, a solution, conclusion, works
cited, visuals and examples. The first document and the second document had each of these
qualities. Both documents had a header containing the title and the logo of the company. The first
document contained an image of Klebsiella pneumoniae and cultures. The second image contained a
single photo if one lone microorganism. Each document follow the conventions of a white paper.
Since the first document is slightly like an advertisement, their produce is mentioned towards the
end of the document as a way to keep the interests of readers. Neither paper violated the conventions
of a white paper document and as a result, both documents are easy to understand. They are also
very visually appealing and eye catching. These appealing documents are published online and are
easily accessed. Since, these documents are new they are still able

lab report microbiology Essay
Abstract
Dairy food staff such as soft cheese,cream cheese,raw milk,sour cream,yoghurt and probiotic
yoghurt products can be a rich source of diverse lactic acid bacteria.The objective of this lab
practical was to isolate lactic acid bacteria(LAB) form raw milk,establishment of pure cultures of
LAB,identify LAB and phage recovery and enumeration of recoverd phage.Raw milk was chosen as
a sample so as to have a more positive result.To identify bacteria Lab isolated from raw
milk,biochemical,morphological ,physiological and cultural characteristics were employed. The
purification of isolates was done by moving Gram +ve ro ds and cocci shaped bacteria to selective
media MRS and M–17 plates. The isolates were sub cultured till pure ... Show more content on
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Colonies were then selected randomly and the streak plating method employed to purify the stains.
The strains were kept in 2 conditions including at 4°C (for MRS and M17 plates ) and at –20°C (for
M17 and MRS broth) withh by 20% glycerol.
Identification of the bacterial strains:The strains were subjected to gram staining,catalase and spore
formation tests. (Harrigan and McCance, 1976).All Colonies were characterized in MRS and M 17
agars.The strains that gave gram positive and catalse negative results were set aside for further
identification.(Sharpe, 1979).The growth of the bacteria at different temperatures of between
Growth 10–45°C for 3–6 days , resistance to 60°C for 30 min (Sherman test), growth in the presence
of 2 to 6 % NaCl and different pHs (4.5 and 6.5) were used to identify the strains of LAB. Arginine
and asculin hydrolysis,citrate utilistaion, acetone productionformation of gas from glucose and
production of dextran from sucrose were also determined. The starins were then tested for
fermentation of L–arabinose, D–xylose, galactose, D–fructose, sorbitol, lactose, melibiose,
saccharose, D–raffinose, melezitose, mannose and glucose.Bacterial growth in the different
temperatures were confirmed by turbidity change in MRS or M17 after incubation(after 24,48 and
72 hrs).Microbial

Microbiology Unknown Lab Report Essay
Lab12–Medical Microbiology– Part1– Differential Media/Biochemical Tests, Sp2012 (Set all of
your margins to ½")
Purpose: The purpose of this lab is to help you become a little familiar with some of the tests that
can be typically performed in a clinical or research lab facility. These tests may help in determining
a particular pathogen's growth needs.
There are several sections to this lab. Find each section and complete the "Preparing for Class"
sections.
Preparing for class – Day 1
Read in your lab manual about the following agar mediums: Blood Agar (pg 168), EMB Agar (pg
170), Mannitol Salt Agar (MSA)(pg 172) ), MacConkey Agar (pg 174), and PEAAgar (pg 176) to
answer the following:
1. What does the blood agar select for? ... Show more content on Helpwriting.net ...
|bacteria, or |enterococci |
| | | |greenish/gray hue | |
| | | |around | |
|EMB Agar | |Distinguishes bacteria that ferment |Dark blue colonies with|E. coli and P. |
| |Gram–negative bacteria |lactose and or sucrose and those that|green metallic sheen or|aeruginosa |
| | |do not. |pink. | |
|MSAAgar |For organisms that are |Isolates for mannitol fermentation |Yellow color change in
|Staphylococcus aureus |
| |halotolerant. | |surrounding media. |and Staphylococcus |
| | | | |epidermidis |
| | | |

Microbiology Essay
Osmosis
4/13/13
MLT1 Lab 9
Performed at Home
Microbial Growth
There are three types of environments in which cells are located which include isotonic, hypotonic
and hypertonic. In an isotonic environment, the amount of water and solute are the same both inside
and outside of the cell. As water drifts into the a cell, the same amount flows out creating a balanced
environment both inside and outside of the cell. When there is a high level of water on the outside of
the cell and a high amount of solute inside the cell, water will be drawn inside of the cell creating a
hypotonic solution. The increase in water inside the cell causes the cell to become engorged and
erupt. In a ... Show more content on Helpwriting.net ...
The water activity also plays a big role in the microbes ability to survive as most cannot grow in a
water activity level less than 0.91. Based on observations and construction of a data table, it was
shown that the 1% NaCl solution had a water activity level of 0.99, the 7% NaCl solution 0.96 and
the 15% NaCl solution 0.91. Based on the table it was expected that there would be no growth in the
15% NaCl solution as most microbes cannot survive at a water activity level of 0.91. In the S.
cerevisiae specimen, moderate growth was expected and observed based on the knowledge that most
microbes desire this type of environment for growth. The same was expected although a larger
amount of growth was observed for the S. epidermidis specimens in the 1% NaCl solution than
expected. The 1% NaCl solution provided the best environment for the growth of both microbes.
Minimal growth of S. cerevisiae and moderate growth of S. epidermidis was observed from the 7%
NaCl solutions. The S. epidermidis is used to a slightly salty environment on the surface of skin
which may account for the higher growth over S. cerevisiae in this environment. Lastly, no growth
was noted in either specimen of 15% NaCl. This type of environment does not support the growth of
most microbes due to the increase in salt content and the hypertonic environment it creates.
Sucrose Solution/Results Sucrose was not included in

Soil vs Microbiology
TITLE
Lab #4 Soil –vs– Water Microbiology
INTRODUCTION
There are 4 learning goals for this lab:
1. Collect samples and compile data from at least 2 sources (soil; water) of your choice.
2. Identify at least 2 Prokaryotes (bacteria) and 2 Eukaryotes (fungus) in your samples.
3. Research the importance of bacteria and fungus to Earth in a non–medical context.
4. Compile a high–quality, 3+ resource (excluding the lab worksheet), MLA–cited in–text laboratory
report using the scientific method by class due date.
HYPOTHESIS
The purpose of this lab is to:
1. Collect a sample of soil from (your school) on October 27th 2011 and collect a sample of pond
water from (the name of your lake or pond) on October 27th and record the data ... Show more
Microbiology Introduction. 10th Ed.). It was no surprise to me that E–coli were found in the soil
sample because of the geese and E–coli comes from fecal matter of animals. The soil we retrieved
was from the area by the lake and therefore very possible to get a positive result for E–coli. All of
the fungi and bacteria found from the environment share a symbiosis relationship, two organisms
living together in a close association that is beneficial to one or both of them. (Tortora, Funke, and
Case. Microbiology Introduction. 10th Ed.) The relationship that bacteria and fungi share with each
other contributes to the biogeochemical cycle and without bacteria and fungi we could not continue
our existence on our planet "earth.
METHODS AND MATERIALS MATERIALS 1 Becker 1 Nutrient agar plate 1 pair plastic gloves 1
Potato agar plate 1 Staining tray 100ml of distilled water 2 MacConkey Agar Plates 3 Blank slides 3
plastic cups 6 pipettes 95% Grams alcohol Bibulous paper Boat & Scale Bunsen Burner & Flint
Crystal–violet Grams Iodine Incubator of 35⁰ Celsius (silver) Inoculating loop Microscope Pond
water Safranin Soil Tap water Timer Tweezers METHODS Methods performed as per BIO 270 Soil
sample on October 27th 2011 at 11:45 a.m. Water sample on October

Introduction
Microbiology is the study of microorganisms that live unseen by the naked eye. This field delves
into the morphology, physiology, and biochemical aspects of bacteria, viruses, yeast, protozoa and
archaea. Microorganisms play a vital role in every form of life from plants to animals. There are
many branches within the field of microbiology that are broken down into two groups; pure and
applied. The study of pure microbiology includes six main branches; bacteriology, mycology,
phycology, protozoology, virology, and parasitology (Maruthi, n.d.). This subset of microbiology is
used for the purpose of acquiring a better understanding of these organisms. Applied microbiology
includes an array of fields; with medical and industrial microbiology ... Show more content on
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This species of Shigella has been found to have a negative result for lactose fermentation. However,
its ability to ferment lactose is described as late fermentation (Acharya, 2013). Therefore, test results
may come back positive due to the variability in the incubation period. In this study the result was
found to be negative. Since this test varied in the possible results it was not a key component in
distinguishing the unknown organism. This organism does not utilize citrate for its primary carbon
source. It is also a non– motile organism. This particular species of Shigella produces the
decarboxylase enzyme for ornithine. All the other test results coincided with the biochemical
characteristics for this particular

Why I Want To Study Gut Microbiology
STATEMENT OF PURPOSE The emergence of new pathogens from food and water, particularly
bacteria, as well as the recurrence of known food pathogens, has received research attention in
Nutrition and Food Science. The unusual dietary pattern and nutrition affect the microbial
population in the human gut (Probiotic), with an ample effect on the immune system and human
health. To understand the interactions of gut microflora with food and nutrients, and their potential
involvement in disease etiology and human health, novel approaches tailored from various
disciplines are required. The additional concern is the growing number of children who are
overweight and at a risk of obesity, early onset of type–2–diabetes and sedentary behavior. Taken
together ... Show more content on Helpwriting.net ...
This summer, I completed a short term online certificate course in "Introduction to food and health"
offered by Stanford University. This course was focused on sustainable solutions of choosing
healthier foods and practical tips for preparing healthy and nutritious food. I also enrolled in one
more online course to complete the program requirement called "Introductory Human Physiology"
offered by Duke University. Furthermore, in my spare time, I'm learning statistical analysis
softwares such as SAS 9.4 and Python for genomic data

Microbiology Unknown Report
During a lab in my Microbiology class, we got the chance to do what is called an Unknown Report.
It is a report of an unknown sample of bacterial that we performed different tests on to identify the
bacterial species. By following the imporatant steps of aseptic technique in all tests, we were able to
identify the unknown bacteria. These tests involved different petri dish agars, broths, and slants to
know what kind of bacteria we had. As a result, we identified our bacteria as an Escherichia coli.
Each tests gave us an important characteristics of our bacteria that helped us to identify it.
The most imporatant test that we performed was the Gram stain. Gram stain test's meaning is to
differentiate between Gram positive and Gram negative bacteria ... Show more content on
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Therefore, the purpose of this test to identify bacteria based on these features. As a result, we had
white, slime, a little shiny colonies that was shaped as almost a flower.
In addition, we were able to know if the bacteria was positive or negative for the catalase reaction.
Catalase reaction is done by adding hydrogen peroxide–H2O2. If the test was positive, then the
colonies would start forming bubbles, and if it's negative, then it won't. Therefore, in our sample of
the bacteria was a positive catalase reaction because we saw bubbles coming out after adding the
hydrogen peroxide.
Then, we used different agars whether there were selective or differential or even both to gives us
more information about the unknown. One of the most imporatant agar that we used was Mannitol
salt agar, which is both selective and differential medium. Mannitol salt agar is selective for
halophiles and differential for mannitol use. It starts as a pink agar that changes color to yellow or
orange if the bacteria was able to grew on this salty culture and was able to use mannitol as a sugar.
However, our bacteria sample didn't even grew on it; therefore, it didn't change agar color and
stayed

Microbiology Research Paper
Melissa Babajko
Microbiology 214BA
Dr. May
June 6, 2012
Staphylococcus aureus– Is a facultative anaerobic, Gram–positive, salt positive, cocci shaped
bacterium. Staphylococcus aureus is found as normal part of the skin floral in the nasal passages and
on the skin. An estimated twenty percent of people naturally have harmless Staphylococcus aureus
on their skin and are long–term carries for Staphylococcus aureus. Staphylococcus aureus is the
most common strand of Staphylococcus in humans to date, spread through skin to skin contact or
even skin to object contact that an a person infected with Staphylococcus aureus has touched.
Staphylococcus aureus is coagulase positive, which induces clumping of the cells and of the blood.
Staphylococcus ... Show more content on Helpwriting.net ...
(http://www.ncbi.nlm.nih.gov/pubmed/22621239) PMID: 22621239 [PubMed – as supplied by
publisher] May 2012
Streptococcus pneumoniae– Is a Gram–positive bacterium in the shape of a slightly pointed cocci.
They are usually found in pairs as diplococci. Streptococcus pneumoniae are alpha hemolytic
bacterium. Streptococcus pneumoniae have a polysaccharide capsule that acts as a virulence factor
for the organism; along with surface proteins that prevent the activation of complement pathways,
and pili that enable S. pneumoniae to attach to epithelial cells in the upper respiratory tract.
Streptococcus pneumoniae lacks catalase and ferments glucose to lactic acid, like most other
streptococci. However, unlike most other streptococci, it does not display an M protein and it
hydrolyzes insulin, which help distinguish it from other streptococci. Streptococcus pneumoniae is
the most common cause of meningitis in adults and young adults throughout the world and is best
known for causing pneumonia all other the world.
Research Study: Due to a continuing increase in S. pneumoniae's antibiotic resistance, the search for
a better vaccine is ongoing. Research on the Lactococcus lactis bacteria for use as a vaccine is
promising; its production of the pneumococcal surface protein PspA makes it a good candidate for a
mucosal vaccine, which could be administered through the nose instead of an injection (a

Micro 310L: Medical Microbiology Lab
Problem
The objective of a lab notebook in Micro 310L: Medical Microbiology Lab is to "record your
laboratory activities in such a manner that a second, equally technically proficient person could do
the same thing without the aid of outside materials and produce the same results..." (Lemper, n.d.).
In order to write a notebook to accomplish this goal, multiple resources are available to students to
assist them in writing their notebook specifically a notebook packet the instructor created to help
Micro 310L students write a lab notebook. Even though there are resources available, there is still
confusion amongst students about the content of a lab notebook. The interactive slide deck will
guide students through the process of a writing a proper ... Show more content on Helpwriting.net ...
Week 1 – Contact Claudia Lemper (instructor of Micro 310L) to talk about the common mistakes
made by the majority of students, the high points of good lab notebooks, and obtain examples of
good and lab notebooks. I will also ask previous Micro 310L students (Monica Morrison and
Kristina Larsen) for their input on what they wish would have been explained to them before writing
a lab notebook and speak with current Micro 310L students (Mikolina Lowe and Noelle Gray) about
any confusion they still have when writing notebooks.
Week 2 – Create an outline of content for each section and within each slide of the slide deck.
Week 3 – Produce the slide deck using the outline from week 2 and PowerPoint software. The
examples will also be scanned and incorporated into the slide deck. I would also like to include
quotes from Claudia Lemper and the students interviewed to provide advice for lab notebook
writing. I will also reserve a workspace in the library to record the voice

Microbiology Unit 9 Lab Report
During the final experiment for Microbiology will have to figure out the unknown organism given
to us. The organisms will be narrowed down by using skills we have learned throughout the lab this
quarter and the test results will narrow down to a single organism. The reason to perform
experiments that determines the identity of bacterium is to find out how to treat it or what infections
it is causing. In a controlled environment, students learned how to use various methods to determine
how to differentiate between multiple bacteria. This lab report will be detailed steps explaining how
to determine the identity of my unknown organism number 12.
Materials and Methods: During this experiment 4 experiments were used to determine the identity ...
Show more content on Helpwriting.net ...
The sulfur reduction test was followed by the procedure on pages 394–396. The materials used for
the sulfur reduction test includes: SIM tubes, inculcating needles, and the bacteria. The SIM tubes
contain reagents cysteine desulfurase and thiosulfate reductase both producing hydrogen sulfide gas,
which will combine with iron and turn black for an indication of sulfur reduction. Before the start of
the procedure the tubes must be labeled with information including: the name of the organism (or
unknown #12), your name, and date. The following procedure was completed while enforcing a
sterile technique throughout by burning the loop before and after each inculcation. The SIM culture
tube was stab inoculated with the bacteria approximately 1 cm from the bottom of the tube. Once the
tube is inoculated, place the tube in the incubator at 35 degrees Celsius for 24 to 48 hours. After the
time in the incubator the tubes are ready to be observed for results. The results for my organism was
unbranched stab line in a yellow broth, which concludes sulfur is not reduced in this bacteria. After
this test the organisms are narrowed down to Eecherichia coli and Shigella sonnei, which can be
differentiated by using a Hektoen Enteric

Microbiology Unknown Paper
The purpose of this laboratory exercise was to perform tests necessary to be able to distinguish one
microorganism from 10 others. Using a series of biochemical tests and characteristics, unknown #22
was concluded to be Pseudomonas aeruginosa. A dichotomous key was mapped out and used during
this process. Using this provided guidance as well as organization as to what the result may be.
Upon obtaining the unknown organism, it was important to make a streak plate of the bacteria on
TSA. The purpose of doing so ensures that we have pure cultures of the unknown to be used in
further testing and not a mixed culture. The first test used was a gram stain. It is a differential stain
that helps distinguish between gram–positive and gram–negative ... Show more content on
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There was also motility because there was growth away from the point of inoculation. It looked like
an upside down Christmas tree in the tube. The last thing SIM tested for was indole production. It is
produced when the bacteria converts amino acid tryptophan to indole. 5 drops of
dimethylaminobenzaldehyde, or Kovacs reagent, was added to the test tube. Upon addition, if it is
positive for indole, it will turn a red color at the top of the medium. When the unknown was tested,
it did not produce a red color. There was a slight dark red/brown color, but overall the test result was
negative. Lactose and sucrose tests were done, which are very similar to the glucose test. The only
difference is the 1% carbohydrate in the medium. For sucrose, the medium contained sucrose. For
lactose, the medium contained lactose. Both of the test tubes resulted in a K result. There was no
color change to yellow or any gas produced in the inverted test tube. The color did change to an
unusual bright pink, but it did not turn yellow like it would have in the presence of acid. The
unknown was also tested for catalase. Aerobic bacteria produce the enzyme catalase. It breaks
downs hydrogen peroxide into water and oxygen. After smearing an isolated colony of the unknown
on a slide, hydrogen peroxide was added and it resulted in bubbling. Bubbling suggests a positive
test and if there is no bubbling, it is a negative test. A citrate lyase test was also done using citrate
agar. Bacteria

Unknown Organism Report: NWTC Microbiology
Unknown Organism Report
Tiffany Sislo
NWTC Microbiology
Identification The first step toward identifying this unknown organism was to perform a Gram Stain
to differentiate between gram positive and gram negative bacteria. This is an important step because
it directs what the next tests will be. My Gram Stain on sample #12 showed that the bacteria was
gram negative, however, after receiving the results of the OF glucose, H2S, Citrate, Urease and
Motility tests, it was apparent that my Gram Stain was contaminated. I then performed a catalase
test which came back negative, so I ordered a Bacitracin disc, Optochin disc and a CAMP test which
had to be incubated overnight. After receipt of those test results, ... Show more content on
Helpwriting.net ...
VGS does not target the gastrointestinal tract; in fact, it is normal flora in that area of the body so it
is more likely that VGS attempted to fight off the invading organism but wasn't strong enough and
lost the battle. As normal flora, VGS will protect us against invaders because it doesn't want to give
up its home. VGS infections, usually endocarditis or septicemia, do not cause any of the signs and
symptoms related to the mystery illness. VGS does not infect people through contaminated water
supplies, it is an opportunist and would take the opportunity to enter the blood if presented, but it
would not go looking to cause infection. If it did cause infection, it would not cause bloody

Essay about Microbiology Unknown Bacteria
INTRODUCTIONS:
Microorganisms are both beneficial and harmful. These microorganisms are important to humans
because they play a role in the ecology of life, by decomposing wastes, both natural and man–made,
such as creating nitrogen fertilizer at the root zones of certain crops. Other several pathogens that
can cause serious harm, even immediate death due to the diseases or disease causing products they
produce. Overall, microorganisms play an important role in life.
The purpose of this study was to identify the unknown bacterium using biochemical tests and
various methods that had been learned from previous the microbiology laboratory class. Identifying
the unknown bacterium was determined by separating and differentiating possible ... Show more
Then the following differential tests were performed:
Gram Stain Test:
Two smears of the unknown bacterium #5 were inoculated while the second smear was used for a
back up. The unknown bacterium dried for at least forty minutes. After the smears dried, the slides
were heat fixed two times to ensure the stability of the organism. The slide was placed on top of the
staining rack then over the small sink.
The drops of crystal violets, approximately 15 drops, were flooded until the smear were all covered
and then allowing resting for one to two minutes. After two minutes, the slide was titled over the
sink and washed off, with the distilled water bottle, by aiming the stream of water above the smear.
The specimen appeared blue–violet when observed with the naked eye. The drops of Gram's iodine
were applied on the slide until covered and then allowed to react for one minute or more. After the
time elapsed, the slide was rinsed again with distilled water following immediate drops of Gram
stain decolorizer added one drop at a time.
Again, after ten seconds, the slide was rinsed with distilled water to wash off the decolorizer. The
slide was placed back on the staining rack. Approximately ten drops of safranin were covered on the
slide allowing resting for one minute. After one minute, the slide was rinsed one final time on the
small sink followed by blotting the stained slide with Bibulous paper. The slide was placed between
pages of Bibulous paper to help

Microbiology Case Study: The Disease That Is Plaguing Carmen
Microbiology Case Study: Carmen The disease that is plaguing Carmen is caused by the
microorganism Vibreo cholera. V. cholerae is a gram–negative, curved–shaped rod bacterium with a
single flagellum. Naturally waterborne, V. cholerae is highly motile which likely enhances its high
pathogenicity.1 In 1833, Robert Koch was the first to isolate V. cholerae and explain its
transmission.2 V. cholerae is secretes the cholera toxin which invades the human intestinal tract and
activates adenylate cyclase enzyme in the epithelial cells of the gut.3 The activated adenylate
cyclase leads to increased intracellular cyclic AMP production which in turn triggers an efflux of
chloride and electrolytes into the gastrointestinal tract. 3 Infected cells ... Show more content on
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Azithromycin is preferred for treatment of cholera pregnant women and children. 8The antibiotic
tetracycline has been used to successfully treat cholera, however, certain strains are starting to show
resistance to tetracycline, most likely due its widespread use in uninfected populations as a means of
preventing infection. 8 V. cholerae is more resistant to antibiotics due to the double membrane of
gram–negative organisms. There is a vaccination for V. cholerae that is used during outbreaks, but
there is differing data on the vaccine's

Importance Of Microbiology
Importance of Microbiology| in Nursing Agriculture Pharmacy
Advertisement
Microbiology is a subject dealing with microbes and related concepts. Microbiology has come a
long way since discovery of microbes and is presently of great help to mankind. It is used in health
care, food production, diagnosis, production of alcohol, maintenance of sterility and cleanliness etc.
Though the subject was initially limited to study of microbes and their characteristics or properties,
latter it was explored to see all possible applications and benefits to man.
Microbiology was a boon to eradicate mass destructive epidemics like rabies, small pox and many
other infectious diseases.
The present society is so dependent on it that without it there can no ... Show more content on
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for sterilization of manufactured drugs. Microbes are destroyed by sterilization. in search of new
drugs.
IMPORTANCE OF MEDICAL MICROBIOLOGY:
In medicine microbiology is taught to let pupil understand types of microbial diseases; i.e. how
diseases are caused by microbes. Their types like bacterial, viral, fungal etc.
Diagnosis and treatment; Even diagnosis of the disease causing microbe is taught so as to give right
drug and combat infection effectively. The identification of

Microbiology Unknown
Autumn White Biology 258–05 November 26, 2012 Unknown #19 Enterbacteriaceae Enterobacter
aerogenes ABSTRACT The objective of this report was to identify an unknown microorganism
through several differential media tests. Over the course of a couple weeks, ten tests were
performed. First, a gram stain was performed, indicating the bacterium was gram negative. An
aerotolerance test determined that the bacterium was a facultative anaerobe. Next, a negative result
in the methyl red test indicated that no mixed acid fermentation occurred. The DNase test was
performed and yielded a positive result. The SIM test provided two outcomes, that the bacterium did
not reduce sulfur nor produce indole from tryptophan. ... Show more content on Helpwriting.net ...
After incubation, approximately 6–8 drops of methyl red were added Possible observations: If
mixed acid fermentation occurs, the broth will turn red. If mixed acid fermentation does not occur,
the broth will not change its color. DNase Test 1. The bacterium was inoculated with a flamed loop
onto agar containing peptides for soybeans, casein, NaCl and DNA 2. The plate was incubated at
37C for 24 hours Possible observations: If there is a clearing in the agar around the growth, then
DNase is present. If there is not a clearing in the agar, DNase is not present. SIM Test: Tests for
sulfur reduction, indole production from tryptophan, and motility 1. The SIM slant was stabbed with
a flamed needle inoculated with the bacterium 2. The slant was incubated at 37C for 24 hours 3.
After incubation, Kovacs' reagent was added. The Kovacs' reagent will react with any indole present
Possible observations: If sulfur was reduced, there will be black in the medium. If sulfur was not
reduced, there will not be black in the medium. If tryptophan is broken down into indole and
pyruvate, there will be red in the alcohol layer of Kovacs' reagent. If tryptophan does not break
down, then the reagent color will be unchanged. If there is growth radiating from the stab line, there
is motility. If there is no radiating growth, there is no motility. Lysine Decarboxylase: Tests for the
presence of lysine decarboxylase, which breaks down an amino acid, and glucose

Unknown Microbiology Report
The purpose of the following study is to determine where the two unknown bacteria acquired in
Microbiology lab should be classified in regards to temperature, pH level, and osmoregularity. It is
important to classify bacteria in order to identify them. Identification of bacteria is important
because they are not only useful but potentially dangerous as well. The identification of bacteria can
lead to breakthroughs in healthcare regarding treatment of old and new diseases alike. Identifying
bacteria can also be used in many other areas from better crop production through microbial
pesticides to biological warfare. Their uses are endless as are their abilities to evolve and adapt to
changing environments. That is why it is so important ... Show more content on Helpwriting.net ...
For the temperature test each bacteria was placed on a nutrient agar and incubated for either 10, 20,
30, 40, or 50 degrees Celsius for 48 hours. During the pH test, each organism was placed on four
agars varying in pH level from pH 2, 4, 6 and 8 and incubated near 37 degrees Celsius for 48 hours.
For the osmotic pressure test, each organism was placed on four agars one each containing 2%, 5%,
8%, and 11% NaCl concentration levels. These were incubated near 37 degrees Celsius for 48 hours.
The results of the tests are recorded in Tables 1, 2, and 3. All tests were performed according to the
instructions provided in Leboffe & Pierce(1). The biochemical tests used on both unknowns and the
ubiquity are:
1. Temperature
2. Osmolarity
3. pH
Results:
Table 1 The Effect of Temperature on Microbial Growth
Organism 10 degrees Celsius 20 degrees Celsius 30 degrees Celsius 40 degrees Celsius 50 degrees
Celsius Classification
Uninoculated Culture NG NG NG NG NG
UK–R 1 6 7 4 NG Mesophile
UK–W 1 5 6 4 2 Mesophile
UB–1 4 4 5 3 NG Mesophile
Table 2 The Effect of pH on Microbial Growth
Organism pH 4 pH 6 pH 8 ph 10 Classification
Uninoculated Culture NG NG NG NG
UK–R 4 7 8 4 Neutrophile
UK–W 4 6 8 4 Neutrophile
UB–1 1 2 5 3 Neutrophile

Table 3 The Effect of Osmotic Pressure on Microbial Growth
Organism 2% 5% 8% 11% Classification
Uninoculated Culture NG NG NG NG
UK–R 4 3 3 0 Non–halophile
UK–W 4 2 1 0 Non–halophile
UB–1 4 7 3 2 Halophile

Microbiology: Alcaligenes Faecalis Bacteria
Microbiology is a study of small living organisms that are hard to be seen without using the
microscope; such as bacteria, archaea, viruses, and protozoa. Fungi are different, a majority are big
enough for us to see. They're all have a long history of living on Earth, the scientist also believes
they are the first living things that are existing way before mammals or human. Those
microorganisms are everywhere around us, some are harmless and some can cause serious diseases.
The condition and environment are different for every microorganism, some can live in the cold and
a few can live in an area where hardly any living things can survive in. However, the bacteria that I
found the most interesting in is Alcaligenes faecalis bacterium because ... Show more content on
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faecalis is belonged to Alcaligenes genus in Alcaligenaceae family, according to Foundations in
Microbiology: "It is a group of non–fermentative, oxidase–positive, motile bacteria ... Members of
Alcaligenes live primarily in soil and water habitats, and they may also become established as
normal microbiota. The most common clinical species. A. faecalis, is isolated from feces, sputum,
and urine. It is occasionally associated with opportunistic infections such as pneumonia, septicemia,
and meningitis" (pg. 612). A. faecalis bacterium has those characteristics such as tiny size, thin/ rod/
coccobacillus shaped, a light cream color that is growth at room temperature (37 Celsius degree) as
least from 24 to 48 hours to be seen. The bacteria also preferably to growth on nutrient agar slant
broth and medium; the elevation is flat. Base on my observation, it is a gram–negative aerobe
bacteria have motile and flagellated because when I looked under the microscope for gram–stain
with oil immersion lens, and the color of the bacterium is pink. Moreover, Microbacteria: A
Laboratory Manual does provide a chart on page 216 giving all of the important of cultural and
biochemical characteristics about A. faecalis bacterium; litmus milk reaction test results as alkaline,
fermentation including lactose, dextrose, and sucrose are having negative results, majority tests are
negative except citrate test (can be positive or negative), catalase activity, and oxidase activity is
giving positive

Microbiology Essay
One of the most common bacteria known to man is affiliated with the genus Staphylococcus.
Staphylococcus aureus can be described as bacteria that present as gram positive cocci either in
pairs, tetrads, short chains or irregular grape like clusters (2A). With their diameter ranging from 0.5
to 1.5 um, other characteristics that comprise this bacteria include their non–spore forming ability
and nonmotile ways (2A). Defined as facultative anaerobes, these microorganisms are usually
encapsulated(2A) and are a member of the normal flora that resides on humans(2D). In humans, a
common site of habitation would be the nares(2D). The chances of S.aureus colonization are greater
in individuals that are diagnosed with hiv, insulin–dependant ... Show more content on
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An example would be when individuals who are asymptomatic nasal carriers of this bacteria
accidentally autoinoculate another part of their body, resulting in them now being infected (DIC).
An usual route that can also be taken to assist in the spread of S.aureus is through fomites(3a).
Though highly unlikely, sharing towels was once the cause of staphylococcal infections in a high
school football team(3a). The different opportunities presented for the dissemination of the
microorganism are the factors contributing to its transportation throughout communities.
To increase their effectiveness, many organisms resort to producing molecules called virulence
factors. These molecules prove to be beneficial to the pathogen by strengthening their pathogenic
capabilities. Through many examinations and dissections performed on S.aureus, it was revealed
that that bacteria itself was home to a wide range of virulence factors. Being the most common, the
pathogen is comprised of surface adhesions whose main job is to regulate the attachment of the
bacteria to its target tissues(4b). This in turn helps guarantee the bacteria a better chance of invading
the tissue and causing an infection. In addition, another important factor is the polysaccharide
capsule(4c). Even though many variations of the capsule have been reported, type 5 and 8 have been
deemed to play a more

Unknown Report On Microbiology And The Epidemiology Of An...
Kelsey Nolte
Microbiology
Otero Junior College
Mr. McClure
Fall Semester 2014
Unknown Report
Introduction
The definition of Microbiology is the branch of science that deals with microorganisms.
Microorganisms are very small organisms that require the use of a micro scope to visualize them,
which are bacterium, viruses, fungi (the most common) and others which are not so common such as
parasites. Microorganisms are an essential element to the field of microbiology because it allows
researchers in the field to find specific illness caused by a specific organism, cures for illnesses,
medicine, history of an organism, and the epidemiology of an organism.
In the year 1665 an English scientist, Robert Hooke built the microscope and observed slices of cork
and came up with the name cells to describe the arrangement of small box spaces within the cork. It
wasn't until Anton van Leeuwenhoek, that observed living organisms under a microscope, which he
built and had a power of 300X. Leeuwenhoek was amazed by the fact of being able to view
"animalcules"; he would sab a sample of water making people sick and samples of his own mouth.
Over the years he would have viewed all the major organisms of microbiology, such as; protozoa,
algae, yeast, fungi and bacteria in spherical, rod and spiral shapes. Leeuwenhoek did not sell his
microscope or foster the development/ study of microbiology It was not until the later scientists who
discovered the germ theory(Theodor Schwann), Redi,

Microbiology Unknown Report
Microbiology Unknown Report On June 25th, 2015 I chose the test tube labeled #19. This test tube
contained an unknown bacterium, and the purpose was to determine the unknown bacterium by the
end of the semester. Throughout the course, I ran a series of differential tests that would lead me to
discovering the characteristics of my unknown. These tests that I will discuss in this paper are vital
to understanding the biochemical mechanisms that different bacteria can perform, therefore helping
me identify my bacterium based on molecular differences. During the course of this paper, I will
refer to my unknown as unk#19. Also, I would note that aseptic technique was performed
throughout the entire experiment and subcultures were regularly made. ... Show more content on
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To do this, one must use a series of biochemical tests. These tests will investigate the bacterium's
ability to use available enzymes and degradation of specific carbohydrates, lipids, proteins and
amino acids. The use of these organic compounds will produce byproducts that can be observed to
determine the metabolism of the unknown bacterium. One of the first biochemical tests that I
prepared was the S.I.M. test, which is a combination of three tests in one test tube. The "S"
represents sulfide for the sulfur reduction test. This individual experiment detects hydrogen sulfide
production. If the unknown bacterium has either cysteine desulfurase or thiosulfate reductase it will
be able to reduce sulfur to a hydrogen sulfide gas. Once H2S is produced, it combines with the
ferrous ammonium sulfate, forming a black ferrous sulfide precipitate that can be seen along the
original stab line; the presence of black along the stab line would indicate a positive result. This test
can also be used to detect the presence or absence of motility. This observation is what makes up the
"M" in the S.I.M. test for motility. The only thing that needs to be done for this test is observation. If
there is growth away from the stab line, then that indicated that the unknown bacterium is motile. If
there is no growth away from the stab line, then that indicates no motility and a negative result.
Unk#19 presented with black precipitate as well as growth away from the stab line. After
completing the motility and sulfide tests, I could then perform the indole test. The purpose of this
test is to find if the unknown bacterium contains the enzyme tryptophanase can break down the
amino acid, tryptophan, into its three metabolic ingredients: indole, pyruvic acid, and ammonia. If
the bacterium contains tryptophanase, they will then use ammonia and pyruvic acid for nutritional
needs,

Environmental Microbiology Lab Report

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Environmental Microbiology Lab Report