Metabolism on Substrates other than glucose

Question 1

cellulose is made from?

the three required enzymes?

Answer 1

B-1,4-linked glucose units lacking side chains

three required enyzmes:

1) endo-B glucanase
2) Exo-B-glucanase (B-glucan)
3) Cellobiase (B-glucosidase)

Question 2

Four main mechanistic classes for proteases?

How is the active sites of each protease set up?

Answer 2

serine, cysteine, aspartyl, and metalloproteases

active sites of serine and cysteine proteases, the eponymous residue is usuall paried with proton-withdrawing group to promote nucleophilic attack peptide bond

aspartyland metalloproteases activate water moleucle to serve as the nucleophile, rather than using functional group of the enzyme itself.

Question 3

what allows a bacteria to thrive in a new environment?

Answer 3

acquisition of virulence factors along with metabolic capabilities allow bacteria to thrive in a new environment.

Question 4

tryptophan

ring cleavage:

which are chromosomal?

and which are associated with plasmids?

Answer 4

ortho (between hydroxyls)

meta (adjacent to hydroxyl)

ortho cleavage pathways are chromosomal

meta associated with plasmids

Question 5

dioxygenases or oxidases incorporate what?

Answer 5

incorporate both atoms of molecular oxygen

and open up benzene rings

Question 6

gentisate pathway?

*key about this pathway?

Answer 6

3-hydroxybenzoate

gentisate

maleylpyruvate

fumarylpyruvate

fumarate

* key is that gentisate has a carbon ring that is opened by the end of the pathway.

Question 7

tryptophanase does what?

Answer 7

take water and tryptophan and creates indole as well as pyruvate and ammonium

Question 8

if bacteria dont produce tryptophanase then?

Answer 8

if the bacteria dont produce tryptophanase then it is incapable of producing indole from tryptophan, and therefore formed less persister cells.

Question 9

What two E. coli pathways are stimulated by indole?

Answer 9

1) phage-shock response
2) oxidative stress response

Question 10

what promotes Vibrio cholerae colonization of the intestinal tract?

Why what does it contain?

what does this in turn do?

What selectively inhibits coliforms but also allows Salmonella to utilize ethanolamine or 1,2-propanediol as carbon sources for anaerobic growth in the lumen?

Answer 10

Sialic Acid

contains genes encoding a neuraminidase and proteins necessary for transport and catabolism of sialic acids

in turn it allows V. cholera to release cholera toxin which then binds to the host intestinal epithelial cells 0165 and 0170

Thiosulfate