Chapter 24:

Question 1

Know the chemical intermediates of reduction of N2 to NH3.

Question 2

Know the source of electrons for N2 fixation.

Question 3

Know the purpose of ATP in the nitrogenase reaction.

Question 4

Describe the formation of glutamate from α-ketoglutarate and NH4+.

Question 5

Describe how the S isomer of glutamate is made (as opposed to a racemic mixture).

Question 6

Explain the difference between “Glutamate dehydrogenase only” and “Gln synthetase /
Glu synthase” as ways of incorporating NH3 into α-ketoglutarate (why two ways).

Question 7

Know the sources of carbon skeletons for amino acid synthesis. Know at least one from
each of three pathways (glycolysis, pentose phosphate, and citric acid cycle).

Question 8

Describe what is meant by essential amino acid, be able to name at least 4 of them.

Question 9

Know the function of the conserved Lys and the conserved Arg in transaminase.

Question 10

Explain the regulation when two amino acids are made from a common precursor 9we
discussed Val and Ile from hydroxyethyl-TPP.