This document provides an overview of the ultrastructure and characteristic features of bacteria. It discusses the general morphology of bacteria and describes several key structures. Bacteria have a cell wall, plasma membrane, cytoplasm, ribosomes, and may contain structures like flagella, pili, capsules, and plasmids. The document contrasts gram positive and gram negative bacterial cell walls. It provides details on the components and functions of bacterial cell membranes, peptidoglycan, teichoic acids, and lipopolysaccharides. Reproduction, nutrition, distribution, resistance and size of bacterial cells are also summarized.
Bacteria are microscopic, single-celled organisms that thrive in diverse environments. These organisms can live in soil, the ocean and inside the human gut. Humans' relationship with bacteria is complex. Sometimes bacteria lend us a helping hand, such as by curdling milk into yogurt or helping with our digestion.
Pure Culture Technique
Culture : Act of cultivating microorganisms or the microorganisms that are cultivated.
Mixed culture : more than one microorganism
Pure culture : containing a single species of organism.
Common isolation techniques:
1. Streak plate method
2. Pour plate method
3. Spread plate method
4. Roll tube method
GROWTH OF BACTERIA CANNOT BE MEASURED DIRECTLY BY SEEING THEM AS THEY ARE MICROSCOPIC STRUCTURES THEREFORE WE HAVE TO USE SEVERAL METHODS WHICH ARE DESCRIBED IN THIS PRESENTATION
Bacteria are microscopic, single-celled organisms that thrive in diverse environments. These organisms can live in soil, the ocean and inside the human gut. Humans' relationship with bacteria is complex. Sometimes bacteria lend us a helping hand, such as by curdling milk into yogurt or helping with our digestion.
Pure Culture Technique
Culture : Act of cultivating microorganisms or the microorganisms that are cultivated.
Mixed culture : more than one microorganism
Pure culture : containing a single species of organism.
Common isolation techniques:
1. Streak plate method
2. Pour plate method
3. Spread plate method
4. Roll tube method
GROWTH OF BACTERIA CANNOT BE MEASURED DIRECTLY BY SEEING THEM AS THEY ARE MICROSCOPIC STRUCTURES THEREFORE WE HAVE TO USE SEVERAL METHODS WHICH ARE DESCRIBED IN THIS PRESENTATION
Bergey's Manual and it's classification. A brief concised presentation prepared for taking seminar and classes.
Volume II (Edition 2) described more in detail.
Pharmaceutical Microbiology Unit-2
Identification of Bacteria using staining techniques(Simple, Gram’s & Acid fast staining) and Biochemical Test (IMViC).1. INDOLE TEST 2. METHYL RED (MR) TEST 3. VOGES-PROSKAUR (VP) TEST 4. CITRATE UTILIZATION TEST
Morphology, Classification, Cultivation and Replication of VirusKrutika Pardeshi
This presentation is Useful for B. Pharmacy SEM III Students to study the Topic Fungi According to PCI Syllabus.
It Consist of Morpholoy of Fungi, Cultivation , Replication and Classification of Virud
Types of spoilage, factors affecting the microbial spoilage of pharmaceutical...Ms. Pooja Bhandare
PHARMACEUTICAL MICROBIOLOGY (BP303T)Unit-V Part-1
Types of spoilage, factors affecting the microbial spoilage of pharmaceutical products, source and type of contaminants. Introduction: Defintion Types of Microbial Spoilage:
1. Infection induced due to contaminated pharmaceutical products: Table no. 1.1 Common pathogens spoiling pharmaceutical products:
2. Physicochemical spoilage –
i) Viable growth ii) Gas production
iii) Colouration / Decolouration
iv) Odour formation
v) Taste change
3. Physical Spoilage:
Cracking of emulsion:
Odor changes
4. Biological spoilage:
Microbial Toxins
Microbial Metabolites
5. Chemical spoilage: Table 1.2 Susceptibility of pharmaceutical ingredients to microbial contamination
Factors affecting microbial spoilage
Size of contaminant inoculum
Nutritional factors
Moisture content
pH
Storage temperature
Redox potential
Packaging design
Sources and Types Of Contamination:
Personnel,
Poor facility design,
Incoming ventilation air,
Machinery and other equipment for production,
Raw material and semi-finished material,
Packaging material,
Utilities,
Different media used in the production process as well as for cleaning and Cleanroom clothing.
Economic importance of bacteria
#Economic importance of bacteria
#Bacteria : economically important as these microorganisms are used by humans for many purposes.
#Beneficial uses of bacteria
#Genetic engineering :
#Biotechnology :
#Food processing :
#Bioremediation
#Industry importance of bacteria
#Fiber industry:
#Medicine (probiotics)
#Agriculture importance
Bergey's Manual and it's classification. A brief concised presentation prepared for taking seminar and classes.
Volume II (Edition 2) described more in detail.
Pharmaceutical Microbiology Unit-2
Identification of Bacteria using staining techniques(Simple, Gram’s & Acid fast staining) and Biochemical Test (IMViC).1. INDOLE TEST 2. METHYL RED (MR) TEST 3. VOGES-PROSKAUR (VP) TEST 4. CITRATE UTILIZATION TEST
Morphology, Classification, Cultivation and Replication of VirusKrutika Pardeshi
This presentation is Useful for B. Pharmacy SEM III Students to study the Topic Fungi According to PCI Syllabus.
It Consist of Morpholoy of Fungi, Cultivation , Replication and Classification of Virud
Types of spoilage, factors affecting the microbial spoilage of pharmaceutical...Ms. Pooja Bhandare
PHARMACEUTICAL MICROBIOLOGY (BP303T)Unit-V Part-1
Types of spoilage, factors affecting the microbial spoilage of pharmaceutical products, source and type of contaminants. Introduction: Defintion Types of Microbial Spoilage:
1. Infection induced due to contaminated pharmaceutical products: Table no. 1.1 Common pathogens spoiling pharmaceutical products:
2. Physicochemical spoilage –
i) Viable growth ii) Gas production
iii) Colouration / Decolouration
iv) Odour formation
v) Taste change
3. Physical Spoilage:
Cracking of emulsion:
Odor changes
4. Biological spoilage:
Microbial Toxins
Microbial Metabolites
5. Chemical spoilage: Table 1.2 Susceptibility of pharmaceutical ingredients to microbial contamination
Factors affecting microbial spoilage
Size of contaminant inoculum
Nutritional factors
Moisture content
pH
Storage temperature
Redox potential
Packaging design
Sources and Types Of Contamination:
Personnel,
Poor facility design,
Incoming ventilation air,
Machinery and other equipment for production,
Raw material and semi-finished material,
Packaging material,
Utilities,
Different media used in the production process as well as for cleaning and Cleanroom clothing.
Economic importance of bacteria
#Economic importance of bacteria
#Bacteria : economically important as these microorganisms are used by humans for many purposes.
#Beneficial uses of bacteria
#Genetic engineering :
#Biotechnology :
#Food processing :
#Bioremediation
#Industry importance of bacteria
#Fiber industry:
#Medicine (probiotics)
#Agriculture importance
Bacteria are small single-celled organisms. Bacteria are found almost everywhere on Earth and are vital to the planet's ecosystems. Some species can live under extreme conditions of temperature and pressure. The human body is full of bacteria, and in fact is estimated to contain more bacterial cells than human cells.
Introduction to microbiology, Bacterial Cell wall, Difference between Gram p...Zunaira Gillani
Introduction to microbiology, Brief History of Microbiology, Structure of Bacteria, Size and Shape of Bacteria,Bacterial Cell wall, Difference between Gram positive and Gram negative, Fungi , Classification of fungi, Structure and Characteristics of fungi, , Algae, Types of Algae, Protozoan, Virus, virion, Examples of virus
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
2. General aspects & Morphology of Bacteria:
Bacteria are single cellular microscopic organisms. The study of bacteria
is known as bacteriology and it is a branch of microbiology. The singular
world of bacteria is bacterium. Bacteria have been grouped into
prokaryotic, which means absence of nucleus.
Cell Wall :
Cell walls of bacteria are made up of glycoprotein murein.
The main function of cell wall is it helps in providing support, mechanical
strength and rigidity to cell.
It protects cell from bursting in a hypotonic medium.
Gram staining bacteria are a method of differentiating bacterial species
into two large groups, which are based on their chemical and physical
properties of their cell wall.
3. Gram positive bacteria: Those bacteria when they are stained in gram
stain results in purple colour.
Gram negative bacteria: Those bacteria when they are stained in gram
stain results in pink colour.
Plasma Membrane:
It is also known as cytoplasmic membrane (or) cell membrane.
It is composed of phospholipids, proteins and carbohydrates, forming a
fluid-mosaic.
It helps in transportation of substances including removal of wastes
from the body.
It helps in providing a mechanical barrier to the cell.
Plasma membrane acts as a semi permeable membrane, which allows
only selected material to move inside and outside of the cell.
4. Cytoplasm:
Helps in cellular growth, metabolism and replication.
Cytoplasm is the store houses of all the chemicals and components that are
used to sustain the life of a bacterium.
Ribosome:
A tiny granule made up of RNA and proteins.
They are the site of protein synthesis.
They are freely floating structures that helps in transferring the genetic
code.
Plasmid:
Plasmids are small circle of DNA.
Bacterial cells have many plasmids.
Plasmids are used to exchange DNA between the bacterial cells.
5. Flagella: It is a rigid rotating tail.
It helps the cell to move in clockwise and anticlockwise, forward and also helps the
cell to spin.
The rotation is powered by H+ gradient across the cell membrane.
Pilli:
Short protein appendages.
Smaller than flagella.
Fixes bacteria to surfaces.
It also helps in reproduction during conjugation.
Capsule:
Capsule is a kind of slime layer, which covers the outside of the cell wall.
They are composed of a thick polysaccharide.
It is used to stick cells together and works as a food reserve.
It protects the cell from dryness and from chemicals.
6.
7. Respiration in bacteria:
Anaerobic bacteria: does not require oxygen for respiration.
Aerobic bacteria: require oxygen for respiration.
Locomotion of bacteria: They move around by using their locomotion
organs such as cilia and flagella.
Reproduction in Bacteria: Most organism have one or two methods of
reproduction. But bacteria have many.
a) Asexual reproduction: The bacteria cell undergoes to produce two
bacteria by Binary fission and also by endospores.
b) Sexual reproduction: It is also by two distinct methods like
transformation, conjugation and transduction. In transformation, one
bacteria releases naked DNA strand into the surroundings. The other
bacteria takes up and incorporate into their genome. Transduction happens
due to virus.
13. • Nutrition of bacteria:
• They exhibits different modes of nutrition level such as-
Autotrophic bacteria: These bacteria are able to synthesize their own
food. For e.g.: Phototropic bacteria and chemosynthetic bacteria.
Heterotrophic bacteria: These bacteria are unable to synthesize their own
food, hence they depends on other organic materials. For e.g.:
saprophytic bacteria-these bacteria feeds on dead and decaying matter.
Symbiotic bacteria: These bacteria have a mutual benefit from other
organisms. For e.g.: nitrogen fixing bacteria (or) rhizobium.
Parasitic bacteria: These bacteria are present in plants, animals and
human beings. These bacteria feeds on host cells and causes harm to the
host.
14. • Cosmopolitan distribution: Bacteria are the only organisms
which show cosmopolitan distribution. They are present in
air, water, soil, snow etc. They are present at very cold
(minus degree) temperature regions and also very high
temperature regions. They can live in acidic environment
(helicobacter pyroli) and even basic environment (iron
bacteria).
• Resistance and tolerance: Some of the bacteria are highly
resistant to adverse environments. Even they get
tolerance to harsh chemical and other stuff which destroy
them. Hence irrational use of antibiotics. This has become
so severe that World Health Organization warns of
rampant prevalence of resistant bacteria which can be
incurable by currently available drugs.
15. Size of a Bacterial Cell:
• There are great variations in size of bacteria. They
measure from 0.75 µ to 1.5 µ but on an average each cell
of bacterium measures about 1.25 µ to 2 µ (in diameter).
Some times their size varies due to slide preparation.
• The smallest rod shaped eubacteria is Dialister Pneum-
osintes and measures between 0.15 µm to 3.0 µm size.
Sulphur bacteria, Thiophysa volutans has diameter of
about 18 µm and is considered as largest amongst all
bacteria.
16. Shape and Arrangement of Bacterial Cell
Bacterial cells exhibit greater variation in their shape but usually
four conventional shapes of cell have been recognized.
1. Cocci: Simplest form of bacteria in which bacterium appears like a
spherical cell.
(i) Micrococci: When bacterium appears singly.
(ii) Diplococci: When they appear in pairs of cells.
(iii) Streptococci: When they appear in chain form.
(iv) Tetrad: Arranged in square of four.
(v) Sarcinae: When arranged in cuboidal or in different geometrical or
packet arrangement.
(vi) Staphylococci: Arranged in irregular clusters like bunch of grapes.
17.
18. 2. Rod Shaped: They are also called bacilli and are commonest in microbial
world. They are of two kinds:
(i) Short rods: Very short rods, occurring mostly singly.
(ii) Long rods: Cylindrical shape, are known as Bacilli or rods, occurring singly,
in pairs or in chains.
3. Vibrios: They are curved rods or comma shaped, their curvature is always
less than a half turn.
4. Spirilla: They are curved or spiral shaped cells, their curvature exceeds that
of a half turn. They may be classified as either spirilla or spirochetes.
• Few bacteria actually are flat. For instance, Anthony E. Walsy has
discovered square bacteria living in salt ponds. These bacteria are shaped
like flat, square to rectangular box about 2 µm to 4 µm and only 0.27 µm
thick.
• However, some bacteria are variable in shape and have a single
characteristic form. These are called Pleomorphic (corynbacterium,
Arthrobacter).
19. Examination of bacterial cells with electron microscope
reveals various component structures. Some of these are
outside the cell membrane; others are internal to cell
membrane.
I. Ultrastructure of Bacteria:
20. Structures Outside the Cell Membrane:
a) Capsule:
Some prokaryotic organisms secrete slimy or gummy materials
(exopolymers) on their surface. A variety of these structures
consist of polysaccharides and a few consist proteins. The
more general term glycocalyx is also used.
The glycocalyx is defined as the polysaccharide containing
material lined outside the cell. Composition of layers varies in
different organisms but can contain glycoprotein and different
polysaccharides including polyalcohol and amino sugars.
21. These layers may be thick, or thin, and rigid or flexible, depending
on their chemical nature in specific organism.
The rigid layers are organized in a tight matrix, this form is
referred to Capsule.
Most bacterial capsules are composed of polysaccharides. Capsules
composed of single kind of sugar are termed homopolysaccharides;
are usually synthesized outside the cell from disaccharides by
exocellular enzyme. Other capsules are composed of several types
of sugar and are termed as heteropolysaccharides, for example,
capsule of Klebsiella pneumoniae.
A few capsules are polypeptides. For example B. anthracis, is
composed entirely of a polymer of glutamic acids.
22. a) Functions of Capsule:
Capsule is not essential for survival of organism under
favourable growth conditions. It, however, provides
protection in un-favourable environments. Presence of
capsules is of importance in disease causing ability of
some bacteria.
The in-capsulated strains of the bacterium are protected
from phagocytosis and take part in virulence in addition
because outer polysaccharide layer bounds a significant
amount of water so it is resistant to desiccation.
23. b) Flagella:
Most motile prokaryotes move by use of flagella thread
like locomotors appendages, extending outwards from the
cell membrane and cell wall.
Bacterial flagella are slender, rigid structures, about 20
nm across and up-to 15 to 20 µ m long.
Flagella are so thin that they cannot be observed directly
with bright field microscope. But must be stained with
special techniques designed to increase their thickness.
24. Bacteria species often differ distinctively in their patterns
of flagella distribution and these patterns are useful in
identifying bacteria. Mono-trichous bacteria have one polar
flagellum. Amphi-trichous bacteria have either singe or
duster of flagellum at both pole.
In contrast, Lopho-trichous bacteria, have a cluster of
flagella at one ends. Bacteria surrounded by lateral flagella
are Peri-trichous.
25. c) Flagella Ultra-Structure:
Transmission electron microscope studies have shown
that flagellar apparatus is made up of three distinct
regions:
(1) The outermost region is filament which is extended
from the cell surface to tips.
(2) Basal bodies consist of small central rods inserted
into cells
(3) A short curved segment, the flagellar hook, links the
filament to basal bodies and acts as flexible coupling.
26.
27. The filament is a hollow, rigid cylinder made up of protein subunits
flagellin which ranges in molecular weight from 30,000 Dalton to
6,000 dalton, depending on the bacterial species.
Hook and basal bodies are quite different from filaments. Basal body
is more complex part of flagellum. In E. coli and most Gram-negative
bacteria, basal bodies bear 2 pairs of ring, outer pair (L and P ring)
is situated at the level of outer membrane and inner pair (S and M
ring) is located near the level of cell membrane.
The outer L and P ring associates with lipopolysaccharides and
peptidoglycan layer respectively. Inner M ring contacts the plasma
membrane while S ring lies just above attached to inner surface of
peptidoglycan,. Flagella of Gram-positive bacteria have only lower S
and M ring.
28. d) Fimbriae or Pili:
Some bacteria mostly (Gram negative bacilli) contain, non-flagellated,
extremely fine appendages called fimbriae or pile. The filament of
pilus is straight and diameter is 7 nm. It is made up of pilin protein.
Molecular weight is 17,000.
Pili are non-motile but adhesive structure. They enable the bacteria
to stick firmly to other bacteria, to a surface or to some eukaryotic
such as mold plants, plants and animal cells including RBC and
epithelial cells of elementary, respiratory and urinary tracts.
Pilli help in conjugation (e.q. F. pili or sex pili) of male bacteria, in
the attachment of pathogenic bacteria to their host cell. Pile are
known to be coded by the genes of plasmid that determine cell
capacity to carry out conjugative genetic exchange with other cells.
29.
30. • Some Gram-positive bacteria have tubular unicellular and rigid
appendage of singe protein moity called spinae. They are
known to help the bacterial cell to tolerate some environmental
conditions such as salinity, pH and temperature etc.
e) Spinae:
f) Mesosomes:
• They are in-foldings of plasma membrane found in some
bacterial cells.
• It contains enzyme for performing respiration and
pigments for photosynthesis.
31. Structure of Cell Membrane
Cell membrane is a thin structure, it surrounds the cell; about
8 nm thick. This structure is critical barrier separating the
inside of cell from environment.
Biological membrane, is composed of Phospholipids (20 - 30
%) and proteins (60 - 70 %). The phospholipids form a bilayer
in which the proteins are strongly held (integral proteins) and
these proteins can be removed only by destruction of the
membranes, as with treatment by detergents.
Other proteins are loosely attached (Peripheral proteins) can
be removed by mild treatment such as osmotic shock. The lipid
matrix of membrane has fluidity, allowing the components to
move around laterally. Fluidity is essential for various
membrane functions.
32.
33. Components of Bacterial Cell Wall:
On the basis of cell wall composition, bacteria are classified into
two major group i.e., Gram Positive and gram negative. The two
different cell wall types can be identified by differential stain
known as the Gram stain. After applying this technique; the gram
positive bacteria will stain purple, while the gram negative
bacteria will stain pink.
Gram positive cell wall composition:
Peptidoglycan
Lipid
Teichoic acid
35. Peptidoglycan Component
It is an ingredient that both bacterial cell walls have in common.
Peptidoglycan is porous cross linked polymer which is responsible for strength of
cell wall.
Peptidoglycan is composed of three components.
Glycan backbone
Tetra-peptide side chain (chain of 4 amino acids) linked to NAM
Peptide cross linkage
Glycan backbone is the repeated unit of N-acetyl muramic acid (NAM) and N-
acetyl glycosamine (NAG) linked by β-glycosidic bond.
The glycan backbone are cross linked by tetra-peptide linkage. The tetra-peptide
are only found in NAM.
More than 100 peptidoglycan are known with the diversity focused on the
chemistry of peptide cross linkage and inter-bridge.
Although the peptidoglycan chemistry vary from organism to organism the glycan
backbone i.e., NAG-NAM is same in all species of bacteria.
36.
37. Teichoic Acids:
Teichoic acid is water soluble polymer of glycerol, which is
embedded within the peptidoglycan layers, present in gram
positive bacteria.
It constitutes about 50% of dry weight of cell wall.
It is the major surface antigen of gram positive bacteria.
It contributes to the overall rigidity of the cell wall, which is
important for the maintenance of the cell shape, particularly in
rod-shaped organisms.
Teichoic acids can either be covalently linked to peptidoglycan
(wall teichoic acids or WTA) or connected to the cell membrane
via a lipid anchor, in which case it is referred to as lipo-teichoic
acid.
38. Lipo-polysaccarides (LPS)
LPS is attached to outer membrane by hydrophobic bond and is
synthesized in cytoplasmic membrane and transported to outer-
membrane.
It contributes net -ve charge for the cell, helping to stabilize the
outer membrane, and providing protection from certain chemical
substances by physically blocking access to other parts of the cell
wall.
In addition, LPS plays a role in the host response to pathogenic gram
negative bacteria.
LPS is composed of lipid-A and polysaccharide.
Lipid-A: it is phosphorylated glucosamine disaccharide.
Polysaccharide: it consists of core-polysaccharide and O-
polysaccharide.