Bacterial Anatomy And Physiology Flashcards
Capsule of bacteria is
Tough/well demarcated
Prevents phagocytosis by preventing Opsonization
Slime layer of bacteria is
Very Loose or undemarcated
Capsule and Slime layer both present in which organism
Streptococcus Salivaris
Organisms containing Capsule
Pretty and Nice Capsules
Streptococcus pneumoniae
Klebsiella pneumoniae
Bordetella pertussis
Vibrio Parahemolyticus
Clostridium perfringes
Yersinia pestis
Neisseria meningicoccus
Hemophilus influenza
Cryptococcus
Staphylococcus aureus
Bacillus anthracis
All capsules are made up of
Polysaccharides
Which bacteria capsules are not made up of Polysaccharides
Yersinia pestis - F1 PEPTIDE
B. Anthracis - Polypeptide
S. Pyogenes - Hyaluronic acid capsule
Which organism have microcapsule
S. Aureus
Demonstration of capsule is done by
Mc Fadyeans Reaction
Quellung Reaction/Neufeld Reaction
Mc Fadyean’s Reaction
Used for demonstration of Capsule
Add Polychrome Methylene blue - Purple color around capsule
Example - B. Anthracis
Quellung Reaction
For demonstration of capsule
Capsule Antigen + add Antisera - results in swelling around capsule
Example - Pneumococcus
3 A’s of Slime layer
Antibiotic resistance
Adherence
Anti phagocytic
Difference in thickness between gram Positive and Negative
Gram +ve - 100 layers thick
Gram -ve - 1-2 layer thickness
Difference in lipid content in Gram positive and negative
Gram Positive - 2-5%
Gram Negative - 15-50%
Composition of Gram Positive Cell wall
Peptidoglycan
Lipoproteins
Teichoic acid
Composition of cell wall of Gram negative organisms
Lipopolysaccharides
Lipoprotein
Peptidoglycan
Outer membrane, Periplasmic space and Porins are seen in cell wall of which organisms
Gram Negative organisms
Regions of Lipopolysaccharides
OPA
Region 1 - O antigen (Most variable)
Region 2 - Core Polysaccharide
Region 3 - Lipid A (endotoxin activities)
Composition of Tetrapeptide chain of Gram Positive Organisms
AGLA
Alanine
Glutamine
Lysine
Alanine
Pentapeptide mass bridge is seen in
Gram Positive Organisms
Demonstration of cell wall is done by
RMP Dr
Reaction with Antibody
Mechanical rupture of cell/Microdissection
Palsmolysis
Dr - Differential staining
Endotoxins are usually seen in which organisms
Gram negative Bacteria
Only gram Positive Organism containing Endotoxin
Listeria
Exotoxin can be seen in which organisms
Both gram Positive and Negative
Effect of heat on Endotoxin and Exotoxin
Endotoxin - Heat stable
Exotoxin - Heat liable
Endotoxins and Exotoxin are made up of
Endotoxin - Lipopolysaccharides
Exotoxin - Proteins
Antigenicity of Endotoxin and Exotoxin
Endotoxin - Low antigenicity
Exotoxin - High Antigenicity
Effect of Endotoxin and Exotoxin
Endotoxin - Constant effect
Exotoxin - Variable effect
Endotoxin and Exotoxin are released on
Endotoxin - released on lysis of cells
Exotoxin - released as secretions except Botulinum toxin
Which type of toxin is need in large amount to create efftects
Endotoxin
Types of L form
Stable L form
Unstable L form
Stable L form means
Unable to revert to original form
Ex - Mycoplasma
Unstable L form means
Lose their cell wall with penicillin
Can revert back to original form
Types of Unstable L forms
Protoplast - seen in gram Positive, entire cell wall is lost
Spheroplast - Gram negative, some part of cell wall remains