M2:T5: Cell wall

Created by

Z.k

Cards (16)

define cell wall 
external structure which determines shape, ridgity and protection
eukarya cell wall has …
algae
fungi: chitin
protozoa and slime moulds = don’t have a cell wall
arch cell wall has …
contain: pseudomerien —> glycan peptides
NAG/NAT
beta 1,3 linkage b/w NAG and NAT - lysoenzymes has no effect
L amino acids
bacterial cell wall has…
overall contains: peptiodglycan, 2 sugars NAG/NAM and glycan chains
2 types
gram +ve
gram -ve
What is the thickness responsible for
Responsible for difference in gram stain reaction
list the effects of antimicrobial substances
lysozyme: digest beta 1,4 glysocidic bonds of NAG/NAM, has sheroplast and protoplast
2. penicillin: targets cell wall and binds to transpetptidase
why do we vary penicillin
to give potency against bacteria
how does penicillin become inactive
when bacteria produces Beta lactamase it breaks bonding between cell wall
transpetide enzyme  
cross links peptidogylcan chains which targets cell wall
archea has
beta 1,3 glysocide linkage between NAG and NAT
L amino acid
spheroplast vs protoplast 
spheroplast: part of cell wall is removed (-ve)
protoplast: complete removal of cell wall (+ve)
common for archea
to contain pseudomurin <— glycine and peptides
polysaccharides, glycoproteins or proteins
gram positive cell wall
1 layer
chemicals: peptidoglycan, teiohic acid (holds membrane), lipoteiohoic acid, mycolic acid, polysaccharide
THICK
no outer membrane
peptidoglycan contains: lysine
bonding: in-direct using interbrige <— glycerine pentapetide
gram -ve cell wall
2 layers
chemicals: lipopol, lipoprotein, peptodylcan, proin protein
THIN
outer membrane
petidoglycan: diamipinalite
bonding: direct
why gram +ve is protoplast and gram -ve is spheroplast
due to lysoenzyme completely breaking down in +ve
outer mem in gram -ve limiting lysoenzyme
why is pencillin not toxic to humans
penicillin stops production of peptidogylcan by preventing cross-linking not toxic to humans as we dont have this