Exam 2

Question 1

What are the three phases of PPG synthesis?

Answer 1

1. Assembly of the ppg
2. transport of PPG components to the outside
3. assembly of the PPG externally

Question 2

What are the three ways LPS is transported?

Answer 2

1) wyz pathway. Translocates lps from cytoplasm to periplasm. Sugars are added to a small chain which is flipped to periplasmic side and added to growing end of the polysaccharide.
2) ABC transport – polysaccharide is made in cytoplasm attached to WecA and then using atp hydrolysis is transported to periplasm
3) synthase dependent “uncommon” .

Question 3

What are the three phases of PPG synthesis?

Answer 3

1) Make subunit in the cytoplasm (NAG-NAM with pentapeptide and a di-phosphate addition)
2) export to periplasmic side
3) add to PPG

Question 4

What is the general structure ot the LPS?

Answer 4

From membrane to exterior:

1) Lipid A region
2) Core polysaccharide
3) O-Polysaccharide

Question 5

what is the EMP pathway?

Answer 5

This is the normal glycolytic pathway.

Question 6

What is the ED pathway

Answer 6

In this pathway less ATP is made in glycolysis. Instead phosphogluconate is converted to one molecule of pyruvate and a molecule of G3P which follows the normal rxn pathway to make another molecule of pyruvate.

Question 7

What is the primary function of the pentose phosphate pathway?

Answer 7

Provides 5 carbon sugars, and precursors to aromatic A.A. biosynthesis ect.

Question 8

Pentose phosphate pathway

Answer 8

Complicated as fuck. Makes 3 carbon, five carbon, 7 carbon, 4 carbon and 6 carbon sugars.

Question 9

What is the glyoxylate shunt?

Answer 9

when isocitrate accumulates it activates the glyoxylate shunt. Isocitrate is made into either glyoxylate –> malate or is made to succinate until isocitrate levels level out.

It is important when organisms are grown on fatty acids or acetate.