The Very Basics Flashcards
Peptidoglycan does what
Provides rigid support
What Structure is unique to gram positives?
Lipoteichoic acid
Also has a lot more Peptidoglycan
What is unique to gram negatives?
Endotoxin/LPS Outer Membrane
Periplasm- separates the cytoplasmic membrane from the peptidoglycan layer
SO, in gram negatives, moving outward from the cytoplasmic membrane we see what in what order?
- Periplasmic space
- Peptidoglycan layer
- a little more periplasmic space
- LPS outer membrane
- Capsule
Gram positives from cytoplasmic membrane?
- Peptidoglycan layer
- Capsule
What is the importance of the capsule?
Protects against phagocytosis
Gram Positive Cocci
Staph and Strep
Gram Negative Cocci
Neisseria (the only one)….I repeat, Neisseria is the ONLY gram negative cocci
Which gram positive bacteria has no cell wall and therefore will not gram stain?
Mycoplasma
Spirochetes?
All Gram negative:
- Leptospira
- Borrelia (lyme)
- Treponema (syphilis)
Problematic Gram Stain Mnemonic
“These Rascals May Microscopically Lack Color”
T- Treponema (too thin)
R- Rickettsia ( intracellular parasite)
M- Mycobacteria ( High Lipids are problematic)
M- Mycoplasma (no cell wall)
L- Legionella
C- Chlamydia
Obligate Aerobes
” Nagging Pests Must Breath”
- Nocardia
- Pseudomonas Aeruginosa
- Mycobacterium TB
- Bacillus
Obligate Anaerobes
“Can’t Breathe Air”
Clostridium
Bacterioides
Actinomyces
Characteristics of Anaerobes: Generally very stinky which is due to the short chain fatty acids they produce, they are anaerobes because they lack catalase and/or superoxide dismutase.
Obligate Intracellulars
Rickettsia and Chlamydia (can’t make their own ATP)
Encapsulated bacteria
SHiN- because shins are hard like capsules
Strep Pneumo
H Influenca
Neisseria Meningitidis
Encapsulated bacteria are cleared how
OPSONIZED and cleared by spleen. Must give vaccines for SHiN organisms to splenectomy pts.
+ e. coli, salmonella, psuedomonas
Transformation
Ability to take up naked DNA from a lysed cell. A major characteristic of the SHiN bacteria
