Types of Normal flora
Association between human and normal flora .
Characteristics of normal flora
Tissue specificity
Specific aadherence
Biofilm formation
Normal flora of skin
Normal flora of oral cavity
Normal flora of conjunctiva
Normal flora of respiratory tract
Normal flora of gastro intestinal tract
Normal flora of urogenital tract
Beneficial effect of normal flora
Harmful effect of normal flora
Disease caused by normal flora
When fresh liquid medium is inoculated with a given number of bacteria and incubated for sufficient period of time, it gives a characteristic growth pattern of bacteria.
If the bacterial population is measured periodically and log of number of viable bacteria is plotted in a graph against time, it gives a characteristic growth curve which is known as growth curve or growth cycle.
Extremophilic organisms are organisms that can survive exremities that are detrimental for other forms of life. Here is a presentation that discuss such microorganisms in detail
Introduction to biofilm
Examples of biofilm
Form of biofilm
Discovery of biofilm
Properties of biofilm
Composition of biofilm
Formation of biofilm
Bacterial biofilm
Impact of biofilm
Problem caused by biofilm
Uses of biofilm
Antibiotic Tolerance/Resistance Of Bacterial Biofilms
Antibiofilm approach
Control strategies of Biofilm
When fresh liquid medium is inoculated with a given number of bacteria and incubated for sufficient period of time, it gives a characteristic growth pattern of bacteria.
If the bacterial population is measured periodically and log of number of viable bacteria is plotted in a graph against time, it gives a characteristic growth curve which is known as growth curve or growth cycle.
Extremophilic organisms are organisms that can survive exremities that are detrimental for other forms of life. Here is a presentation that discuss such microorganisms in detail
Introduction to biofilm
Examples of biofilm
Form of biofilm
Discovery of biofilm
Properties of biofilm
Composition of biofilm
Formation of biofilm
Bacterial biofilm
Impact of biofilm
Problem caused by biofilm
Uses of biofilm
Antibiotic Tolerance/Resistance Of Bacterial Biofilms
Antibiofilm approach
Control strategies of Biofilm
You will learn in this presentation the variety of stains of microorganisms that you can find in the different parts of the human body, including their abundance and implications.
You will learn in this presentation the variety of stains of microorganisms that you can find in the different parts of the human body, including their abundance and implications.
Normal flora is the term used to describe the various bacteria and fungi that are permanent residents of certain
body sites, especially the skin, oropharynx, colon, and
vagina (Tables 6–1 and 6–2). Viruses and parasites (protozoa
and helminths), which are the other major groups of
microorganisms, are usually not considered members of
the normal flora, although they can be present in asymptomatic individuals. The normal flora organisms are often
referred to as commensals. Commensals are organisms
that derive benefit from another host but do not damage
that host. The term human microbiome is often used to
describe the normal flora.
The members of the normal flora play a role both in the
maintenance of health and in the causation of disease in
three significant ways:
(1) They can cause disease, especially in immunocompromised and debilitated individuals. Although these
organisms are nonpathogens in their usual anatomic location, they can be pathogens in other parts of the body.
(2) They constitute a protective host defense mechanism.
The nonpathogenic resident bacteria occupy attachment
sites on the skin and mucosa that can interfere with colonization by pathogenic bacteria. The ability of members of the
normal flora to limit the growth of pathogens is called colonization resistance. If the normal flora is suppressed, pathogens may grow and cause disease. For example, antibiotics
can reduce the normal colonic flora that allows Clostridium
difficile, which is resistant to the antibiotics, to overgrow and
cause pseudomembranous colitis.
(3) They may serve a nutritional function. The intestinal bacteria produce several B vitamins and vitamin K.
Poorly nourished people who are treated with oral antibiotics can have vitamin deficiencies as a result of the reduction in the normal flora. However, since germ-free animals
are well-nourished, the normal flora is not essential for
proper nutrition.
THE HUMAN MICROBIOME
The human microbiome is the term used to describe the
thousands of microbes (“microbiota”) located on the skin,
on mucosal surfaces, and within the lumen of the
TABLE 6–2 Medically Important Members of the Normal Flora
Location Important Organisms1 Less Important Organisms2
Skin Staphylococcus epidermidis Staphylococcus aureus, Corynebacterium (diphtheroids), various streptococci,
Pseudomonas aeruginosa, anaerobes (e.g., Propionibacterium), yeasts (e.g.,
Candida albicans)
Nose S. aureus3 S. epidermidis, Corynebacterium (diphtheroids), various streptococci
Mouth Viridans streptococci Various streptococci, Eikenella corrodens
Dental plaque Streptococcus mutans Prevotella intermedia, Porphyromonas gingivalis
Gingival crevices Various anaerobes (e.g.,
Bacteroides, Fusobacterium,
streptococci, Actinomyces)
Throat Viridans streptococci Various streptococci (including Streptococcus pyogenes and Streptococcus
pneumoniae), Neisseria species, Haemophilus influenzae, S. epidermidis
Colon Bacteroides fragilis, Escherichia
The human microbiome comprises of collective genome of all the microbes residing at various sites in the human body and consisting of communities of a variety of microorganisms, including Eukaryotes, Archaea, Bacteria and the virus that reside in the different body habitat including the skin, the oral cavity, respiratory tract, gastrointestinal tract, urinary tract, reproductive tract etc. We acquire these bacteria during birth and the first year of life, and they live with us throughout our lives.
The human microbiota helps us to keep healthy, but sometimes these bacteria can also be harmful. We need to take good care of our microbiota to avoid the development of some diseases, such as obesity and asthma. We should eat healthy foods that contribute to the development of a healthy microbiota. The study of the human microbiome is important, and it gives an in-depth understanding of the interplay between humans and its indigenous microbiota. This gives valuable insight into further research studies in optimizing these organisms to combating life-threatening diseases.
DEFINITION
RHIZOSPHERE EFFECT
MICROORGANISMS FOUND IN RHIZOSPHERE
FACTORS INFLUENCING THEIR GROWTH AND ACTIVITIES
POSITIVE EFFECT OF RHIZOSPHERIC MICROORGANISMS ON PLANTS
NEGATIVE EFFECT OF RHIZOSPHERIC MICROORGANISMS ON PLANTS
DEFINITION OF PHYLLOSPHERE
PARTS OF PHYLLOSPHERE
MICROORGANISM OF PHYLLOSPHERE
PHYLLOSPHERE MICROORGANISMS OF STEM (CAULOSPHERE)
PHYLLOSPHERE MICROORGANISMS OF LEAVES(PHYLLOPLANE)
PHYLLOSPHERE MICROORGANISMS OF FLOWER (ANTHOSPHERE)
PHYLLOSPHERE MICROORGANISMS OF FRUIT(CARPOSPHERE)
FACTORS INFLUENCING MICROBIAL GROWTH AND ACTIVITIES
POSITIVE EFFECT OF PHYLLOSPHERE MICROORGANISMS
NEGATIVE EFFECT OF PHYLLOSPHERE MICROORGANISMS
Carbon cycle is a biogeochemical in which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere and atmosphere of earth.
In earth’s atmosphere , CO2 is only 0.32%.
The process of photosynthesis, respiration, decomposition move carbon through carbon cycle partly as CO2.
Carbon is the backbone of life on Earth.
SOURCES
CARBON CYCLE
MAJOR DIVISIONS OF CARBON CYCLE
TYPES
SLOW CARBON CYCLE
FAST CARBON CYCLE
CATEGORIES OF CARBON
PROCESS INVOLVED
PHOTOSYNTHESIS
COMBUSTION
RESPIRATION
DECOMPOSITION
MINERALISATION
IMMOBILISATION
ASSIMILATION
IMPORTANCE OF CARBON CYCLE
Mutation
A mutation is a change in the DNA’s nucleotide sequence.
An abrupt shift in the nucleotide sequence causes an organism’s morphological traits to change. Such a change is referred to as a mutation if it is heritable.
So, mutation is defined as any heritable change in the sequence of nucleotide of DNA.
Features
Change in number- it is the change in the number or arrangement of nucleotide sequence of a gene.
It is heritable change in the DNA sequence.
Permanent structural change inherited material DNA effects
Can be harmful/beneficial or have no effects.
Can be sometimes attributed to random chance events.
Can be caused by mistakes during cell division or
May be caused by exposure to DNA damaging agents to the environment such as radiation and Mutagenic chemicals.
Types
Point mutation
-Silent Mutation
-Non sense Mutation
-Mis sense Mutation
Frame shift mutation
Substitution
Addition
Deletion
Causes
MUTAGENS
Physical
Chemical
Biological
ELISA (enzyme-linked immuno sorbent assay) by Pranzly.pptPranzly Rajput
INTRODUCTION
The term ELISA was first used by Engvall & Perlma in 1971.
high sensitivity
useful & powerful method in estimating ng/mL to pg/mL ordered materials in the solution.
Similar To RIA, Except No Radio-labelling.
Alkaline phosphatase, horseradish peroxidase and beta-galactosidase are the enzymes used in the EIA tests.
PRINCIPLE
MATERIAL REQUIRED
REAGENTS
TYPES
NON-COMPETITIVE ELISA
DIRECT ELISA
INDIRECT ELISA
SANDWICH ELISA
COMPETITIVE ELISA
ELISA RESULT
QUALITATIVE
QUANTITATIVE
SEMI-QUANTITATIVE
PRECAUTIONS
PHOSPHATE SOLUBILIZERS
INTRODUCTION
Phosphate SOLUBILIZERS are a group of beneficial micro-organisms capable of breaking down of organic and inorganic insoluble phosphorous compounds to soluble P form that can easily be assimilated by plants.
Phosphorous (P) is a major growth-limiting nutrient, Plants acquire phosphorus from soil solution as phosphate anion.
TYPES
MECHANISM
ISOLATION
INOCULANT PRODUCTION
INOCULANT APPLICATION
ROLE OF PHOSPHATE SOLUBILIZERS
The glutamate family :-
Conversion of a-Ketoglutarate to Glutamate
In the presence of enzyme glutamate dehydrogenase.
Synthesis of Glutamine -two step process.
Synthesis of Proline
Synthesis of Arginine- more complex pathway
Types of organs system.
∆Primary organs
Immature lymphocytes generated in hematopoiesis mature and become committed to a particular antigenic specificity within the primary lymphoid organs
Only after a lymphocytes has matured within a primary lymphoid organ is the cell immunocompetent (capable of mounting an immune response).
T cells arise in the thymus, and in many mammals—humans
-Bone marrow -supports self-renewal and differentiation of hematopoietic stem cells (HSCs) into mature blood cells.
bone marrow is the site of B-cell origin and development
the long bones (femur, humerus), hip bones (ileum), and sternum tend to be the most active
contains several cell types that coordinate HSC development.
-Thymus
∆secondary organs
Lymph nodes and the spleen are the most highly organized of the secondary lymphoid organs and are compartmentalized from the rest of the body by a fibrous capsule.
lymphoid tissue is organized into structures called lymphoid follicles,
Until it is activated by antigen, a lymphoid follicle—called a primary follicle—comprises a network of follicular dendritic cells and small resting B cells.
After an antigenic challenge, a primary follicle becomes a larger secondary follicle—a ring of concentrically packed B lymphocytes surrounding a center (the germinal center)
-Spleen
-Lymph nodes
-Associated tissue
-MALT
-GALT
-BALT
-CALT
Types of immune cells
∆Lymphoid cells
-lymphocytes
constitute 20%–40% of the body’s white blood cells and 99% of the cells in the lymph
continually circulate in the blood and lymph and are capable of migrating into the tissue spaces and lymphoid organs
lymphocytes enlarge into 15 µm-diameter blast cells, called lymphoblasts; these cells have a higher cytoplasm : nucleus ratio and more organellar complexity than small lymphocytes.
Lymphoblasts proliferate and eventually differentiate into-
effector cells or into
memory cells.
* B-lymphocytes
*T-lymphocytes
* Natural killer cells
∆mononuclear phagocytes
The mononuclear phagocytic system consists of monocytes circulating in the blood and macrophages in the tissues.
-macrophages
-monocytes
∆granulocytes cells
Granulocytes are at the front lines of attack during an immune response and are considered part of the innate immune system.
Granulocytes are white blood cells (leukocytes) that are classified as neutrophils, basophils, mast cells, or eosinophils on the basis of differences in cellular morphology and the staining of their characteristic cytoplasmic granules
The cytoplasm of all granulocytes is replete with granules that are released in response to contact with pathogens.
These granules contain a variety of proteins with distinct functions:
Some damage pathogens directly;
some regulate trafficking and activity of other white blood cells, including lymphocytes
-neutrophills
-basophils
-eosinophils
-dendritic cells
-mast cells
∆Phosphorous cycle
∆Sources of phosphorus
-ROCK DEPOSITS (SEDIMENTS)
-AGRICULTURE CROPS CONTAIN 0.05-0.5%
-ORGANIC FORMS- IN FORM OF PHYTIN, PHOSPHOLIPIDS, NUCLEIC ACID, PHOSPHORYLATED SUGAR, COENZYMES, ACID
-ADENOSINE TRIPHOSPHATE(ATP)
-SOIL IS RICH IN ORGANIC PHOSPHOROUS
∆Steps in phosphorus cycle
WEATHERING OF ROCKS
ABSORPTION BY PLANTS
ABSORPTION BY ANIMALS
RETURNING TO THE ENVIRONMENT THROUGH DECOMPOSITION
∆Process involved in phosphorus cycle
ALTERATION OF SOLUBILITY OF INORGANIC COMPOUNDS OF phosphorus.
MINERALISATION
IMMOBILISATION OF PHOSPHOROUS
ASSIMILATION
OXIDATION/REDUCTION
Importance of phosphorus cycle
Factors that affect microbial growth by Pranzly.pptxPranzly Rajput
Intrinsic and extrinsic factors
Intrinsic factors include
Characteristics of the food itself are called intrinsic factors.
These include naturally occurring compounds that influence microbial growth,
MOISTURE CONTENT
pH AND ACIDITY
NUTRIENT CONTENT
BIOLOGICAL STRUCTURE
REDOX POTENTIAL
NATURALLY OCCURING AND ADDED ANTIMICROBIAL
Extrinsic factors are those that refer to the environment surrounding the food.
TYPES OF PACKAGING AND ATMOSPHERES
EFFECT OF TIME/TEMPERATURE CONDITIONS ON MICROBIAL GROWTH
STORAGE AND HOLDING CONDITION
PROCESSING STEPS
antibiotic susceptibility testing
disk diffusion method
Kirby Bauer disc diffusion method
Stokes method
diluted method
agar dilution
test tube dilution
epsilometer test (E test)
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2. • Normal flora are the microorganisms that live on another living Organism
for example (human or animals) or in--animate object without causing
disease.
• The mixture of Organism regularly found at any anatomical site referred to
as normal flora
• Also known as Indigenous microbiota
• They consist of few eukaryotic fungi and protest but bacteria are the most
numerous and obvious microbial component of normal flora
• The human body which contains 1013 cells routinely harbours 1014 bacteria
these bacteria population constitute the normal microflora
INTRODUCTION
3. TYPES
RESIDENT MICROFLORA
•inhabits for extended period
•consists of relatively fixed type of
microorganism regularly found in
given area at a given age
• if disturb it promptly re-
establishes itself
•Example- found in upper
respiratory tract, nose, mouth,
bronchi, trachea, epiglottis
TRANSIENT MICROFLORA
inhabits temporarily
consist of non pathogenic or
potentially pathogenic
microorganisms that inhabit the
skin or mucous membrane for
hours days weeks
it is derived from the environment
does not produce disease and
does not establish itself
permanently on the surface
if resident flora is
disturbed transcend
flora may colonize
Proliferate and
produce disease
4. ASSOCIATION BETWEEN HUMAN AND NORMAL FLORA
• , • .
1. There is a dynamic interaction rather than association mutual indifference both host
and bacteria are thought deserve benefits from each other and their association is
MUTUALISTIC
HUMAN
nutritional and digestive benefits
stimulation of development of
activity immune system
protection against colonization and
infection by pathogenic microbes
NORMAL FLORA
supply nutrients
stable Environment
Protection and transport
2. Benefits some of them are PARASITIC Live at the expense of their host
and 3. some are PATHOGENIC capable of producing disease
• Disease produced by normal flora in their host are endogenous disease
5. • Many endogenous bacterial disease are opportunistic
infection
the Organism must be given a special opportunity of weakness
or let down in the host defense in order to infect.
Example- chronic bronchitis in smokers due to weakened lungs
4. sometimes the relationship between a member of the normal
flora and the host cannot be deciphered (no apparent benefit or
harm to either Organism) is termed as COMMENSAL relationship
Example- it happens with the bacteria which are present in low
number
6. CHARACTERISTICS OF NORMAL FLORA
1.TISSUE SPECIFICITY
• most members prefer to colonize certain tissue and not others and show
the phenomena of TISSUE TROPISM
Bacteria prefer certain tissue for growth host essential nutrients and growth
factors for bacterium like
o Suitable oxygen,
o pH and
o temperature for growth
Example- lactobacillus acidophilus Informally known as doderlein’s bacilli
colonized vagina, because glycogen produced in vagina provide the bacteria
the source of sugar which it ferments to lactic acid and thus results in the
lower pH.
7. 2. SPECIFIC ADHERENCE
• Host bacteria can colonize a specific tissue or side because they can adhere
to it which involves complementary chemical interaction between two
surfaces.
• The receptor on human cells or tissue are usually glycoprotein molecules
located on the host cell or tissue surface
8. 3. BIOFILM FORMATION
• some of the indigenous bacteria are able to construct biofilm on the tissue
surface or they are able to colonize a biofilm built by another bacterial species
• Biofilm usually occurs when one bacterial species attaches specifically or non
specifically to a surface and secrets carbohydrates slime (exopolymer) that
embeds the bacteria and attract other microbes to the biofilm for protection or
nutritional advantage.
Example- formation of dental plaque on the teeth
Plaque is a naturally constructed biofilm in which the consortia of bacteria may
reach a thickness of 300 to 500 cells on the surface of the teeth
9. NORMAL FLORA OF SKIN
• the human is skin is constantly and continuously bombarded by Organism present in the
environment
Density and composition of normal flora of skin varies with the anatomical location
• the higher moisture content of axilla, groin area (between toes) have relatively high
density of bacterial cell as compared to other parts which is fairly low.
• most bacteria are sequestered in sweat glands
• skin microbes found in most superficial layer of the epidermis and upper part of the hair
follicles are gram positive (Staphylococcus and Micrococcus and Corynebacterium like
Propionibacterium
• Staphylococcus and Propionibacterium produce fatty acids that inhibit the growth of fungi
and yeast on the skin.
• If Propionibacterium become trapped in hair follicle it may grow rapidly and cause
inflammation and acne.
10. NORMAL FLORA OF ORAL CAVITY
• The presence of nutrients secretion epithelium debris make it favorable.
• Oral bacteria include Streptococcus, Staphylococcus and Corynebacterium
• Streptococcus salivarius is dominant may make up to 98% of total oral flora
• The eruption of teeth leads to colonization of Streptococcus mutans
• The oral flora also show ANTAGONISM against non indigenous species by
production of inhibitory substances such as fatty acid, peroxides, bacteriocins.
11. NORMAL FLORA OF CONJUNCTIVA
• The conjunctiva is relatively free from Organism due to the flushing action of
tears
• blinking wipes it every few seconds mechanically washing away foreign
objects including bacteria
• BLINKING wipes it every few seconds mechanically washing away foreign
objects including bacteria lacrimal secretion tears also contain bacterial
substances lysozyme
• Newborns are prone to bacterial infection
• Chlamydia and Neisseria might be present on cervical and vagina
• therefore SILVER NITRATE or antibiotic may put on new bonds to avoid
infection after passage through birth canal
12. NORMAL FLORA OF RESPIRATORY TRACT
• Nasal are always colonized by Staphylococcus epidermis,
Corynebacterium and often with Staphylococcus aureus
• the healthy sinuses in contrast are sterile.
• Any bacteria reaching the lower Respiratory tract are swept upward by the
action of mucociliary blanket that line the bronchi to remove by coughing
sneezing swallowing etc.
13. NORMAL FLORA OF GASTROINTESTINAL TRACT
• In humans there are difference in composition of flora which are influenced by
age diet culture condition and the use of antibiotics in upper GI tract of adult
humans
• The esophagus contain only bacteria swallowed with saliva and food
• Because of the high acidity of the gastric juice very few bacteria can be
cultured from normal stomach.
• Helicobacter pylori causes gastric ulcers and can also cause gastric and
duodenal cancer
• At birth the entire intestinal tract is sterile
• But bacteria enters with the first feed in breastfeed- there is 90% of
Bifodobacterium, Enterobacteriaceae and Enterococcus in a small proportion.
14. NORMAL MICROFLORA OF UROGENITAL TRACT
• urine is sterile since the urinary tract is flushed with urine every few hours
microorganism not grow
• Anterior urethra is inhabited by Staphylococcus epidermidis, Enterococcus
faecalis and some alpha-hemolytic Streptococci
• during reproductive life from puberty to menopause the vaginal epithelium
contains glycogen due to the action of circulatory estrogens doderlein’s
bacillus also known as Lactobacillus acidophilus metabolized glycogen to
lactic acid and this is the protective effect of normal flora which prevents
the establishment of bacteria by resulting in lower pH.
• Mycobacterium smegmatis a harmless commensal is found in the smegma
of the genitalia of both men and women.
• During pregnancy there is an increase in Staphylococcus epidermidis ,
doderlein’s bacilli and yeasts.
15. BENEFICIAL EFFECT OF NORMAL FLORA
It synthesize and excrete vitamins-
o enteric bacteria produce vitamin K and B12.
o lactic acid bacteria produce vitamin B
It prevents colonization of pathogen by competing for attachment sites or for
essential nutrients
It antagonizes other bacteria through the production of substances which
inhibit or kill the non indigenous species
o they produce fatty acid peroxides to highly specific bacteriocins which
inhibit and kill other bacteria
Production of natural antibodies and act as an antigen in animal which in turn
induce an immunological response
they stimulate the development of certain tissue
o the cecum lymphatic tissue payers patches in the GI tract immunological
stimulation is poor in germ free animals
16. HARMFUL EFFECT OF NORMAL FLORA
1. BACTERIAL SYNERGISM between members of normal flora and
potential pathogen one Organism help another to grow or survive and
this phenomena is known as cross feeding
• Example- staph-protected infection- penicillin resistant
Staphylococcus shares its resistance drug with other pathogen that
are otherwise susceptible to the drug come
2. Competition for nutrients-Bacteria absorbs some of the host nutrients
for their own needs
3. Introduction of a low grade toxemia minute amount of toxins example
endotoxins are found in circulation these stimulate natural antibodies
4. Maybe a agent of disease cause endogenous disease if they enter
compromised areas.
17. DISEASE CAUSED BY NORMAL FLORA
1.DENTAL PLAQUE- Streptococcus sanguis and Streptococcus
mutans are responsible for plaque formation.
it is initiated by a weak attachment of streptococcal cells to the
salivary glycoproteins forming a pellicle on the surface of the teeth
2. DENTAL CARIES- the destruction of the enamel, cementum of the
teeth due to bacterial activities.
Plaque leads to the formation of lactic acid which de-mineralized
the enamel of the teeth