Enzyme Classification Exam 2

Question 1

oxidoreductases (1)

Answer 1

A(ox) + B (red) A(red) + B(ox)

involving oxidation-reduction pairs; usually have NAD/NADH, FAD/FADH2, 02/H20, or Q/QH2

Question 2

transferases (2)

Answer 2

(A-X) + B A + (B-X)

transfer of one group from one molecule to another

Question 3

hydrolases (3)

Answer 3

(A-B) + H20 A + B
addition of water to cleave a bond
e.g. trypsin, chymotrypsin

Question 4

lyases (4)

Answer 4

A (=) + B (A-B)
addition to a double bond or cleavage to yield a double bond
e.g carbonic anhydrase
CO2 + H20 HCO3(-) + H(+)

Question 5

isomerases (5)

Answer 5

A B

interconversion of 2 isomers; always reversible; not limited to stereoisomers

Question 6

ligases (6)

Answer 6

A + B + NTP (A-B) + NDP + Pi
A + B + NTP (A-B) + NMP + Ppi
Joining two molecules together with input of energy from a nucleoside triphosphate