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Flashcards in Principle of Micro 2 continued Deck (14)
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1

In S. aureus how are NAM and NAG linked

via beta 1-4 linkage

2

for gram positive in S. aureus, how are the chains (NAM and NAM) linked

link is established between the third amino acid on one NAM with the fourth amino acid on the other

3

what are the four amino acids in gram positive

L-alanine
D- glutamine
L-lysine
D- alanine

4

what is the importance of the D-alanine in gram positive

on the NAM that uses the third amino acid for linkage, it releases D-alanine for energy to make the linkage possible

5

what are the four amino acids in gram negative

L-alanine
D-glutamic acid
meso-diaminopimelic acid
D- alanine

D-alanine also released for energy

6

what does lysozyme do

breaks the beta 1,4 linkage weakening the cell wall hence causing cell to burst

7

in gram negative, what is between the peptidogylcan and cell membrane/cytoplasmic membrane

periplasmic gel

8

important structure in the outer membrane of gram negative

LPS endotoxin

9

what anchors the LPS

Lipid A

10

importance of the O polysaccharide

-adhesion at specific sites
-resistance of phagocytosis
-carrier for lipid A
-protection against antibody and complement
-antigenic variation

11

what happens if there is a small change in sequence in the O polysaccharide

significant change in virulence

12

significance of Lipid A from human disease perspective

-powerful biological response modifier
-significant contribution to symptoms and pathology
-B cell mitogen

13

impact of gram positive and gram negative on cellular permeability

gram positive - more permeable
gram negative - less permeable

14

what does mycoplasma have instead of cell wall

sterols and lipids