Biochem (Enzymzes mostly)

Question 1

Phosphorylase, Amylo-1,6 glucosidase debranching enzyme

Answer 1

Mobilization of glucose from glycogen: glycogenolysis

Question 2

Galactokinase; Galactose-1-P uridylytransferase

Answer 2

Galactose to Galactose-1-P, inhibition leads to non-classical galactosemia; galactose1P to UDPgalactose to UDPglucose to Glucose1P, inhibition leads to classical galactosemia

Question 3

Regulators of Glucokinase;PFK1;Pyruvate kinase

Answer 3

Glucose, regulatory subunit; Citrate, ATP -, AMP, Fructose 2,6 Biphosphate +; Fructose 1,6 Biphosphate+, ATP-

Question 4

activation and transport of fatty acids

Answer 4

Palmitoyl CoA ligase, Caritine acyltransferase I,II, Carnitine acylcarnitine translocase

Question 5

Odd chain fatty acid oxidation

Answer 5

Vitamin B12, Propionyl-CoA carboxylase, Biotin, CO2

Question 6

Regulation of pyruvate dehydrogenase

Answer 6

ADP, pyruvate - to inhibitory kinase; NADH, Acetyl CoA inhibitory to activating phosphatase, Intracellular calcium stimluates phosphatase
3 units, located in the mt matrix

Question 7

NADH producting steps in TCA

Answer 7

isocitrate dehydrogenase, alpha ketoglutarte, succinate dehydrogenae (FAD), malate dehydrogenase

Question 8

Reguation of TCA enzmyes

Answer 8

ADP, Ca + for a ketoglutarate and isocitrate dehydrogenase, NADH - for all dehydrogenases

Question 9

Glucose 6 phosphate dehydrogenase

Answer 9

Pentose phosphate pathway, NADPH production

Makes nucleotides or fructose-6-phosphate or glyceraldehyde-3-phosphate

Question 10

Pyruvate Carboxylase

Answer 10

Pyruvate to OAA, Acetyl CoA +

Question 11

Acetyl CoA carboxylase

Answer 11

acetyl co A to malonyl coA, citrate/insulin+, palmitoyl CoA-

Question 12

Glycogen synthase, branching enzyme

Answer 12

Glycogen synthesis

Question 13

Carbamoyl Phosphate Synthetase I

Answer 13

Conversion to carbamoyl phosphate, allosterically upregulated by N-acetyl glutamate whose production is upregulated by arginine

Question 14

arginosuccinate

Answer 14

catalyzes the conversion of arginosuccinate to arginine; byproduct is fumarate

Question 15

AA’s that form OAA

Answer 15

Asp, Asn

Question 16

AA’s that form aKG

Answer 16

Glutamate, glutamine, proline, histidine, arginine

Question 17

AA’s that form pyruvate

Answer 17

alanine, serine, glycine, cysteine, threonine

Question 18

AA’s that form fumarate

Answer 18

phenylalanine, tyrosine

Question 19

AA’s that form succinyl coA

Answer 19

methionine, valine, isoleucine, threonine

Question 20

Nonessential amino acids

Answer 20

Asp, Asn, Glu, Gln, Ala, Ser, Gly, Cys, Arg, Pro, Tyr

Question 21

ribonucleotide reductase

Answer 21

ribonucleoside diphosphate to deoxyribonucleoside diphosphate

Question 22

OXPHOS (membrane transporters and their location)

Answer 22

Adenine nucleotide translocase, Phosphate/pyruvate symporter, Calcium uniporter

Question 23

Competitive inhibition

Answer 23

Bind at substrate recognition site prevent substrate from binding, increasing substrate concentration can overcome competitive inhibitors, increase Km and no effect on Vmax

Question 24

Noncompetitive inhibitors

Answer 24

Interfere with binding site not with primary substrate, lower Vmax

Question 25

Uncompetitive inhibition

Answer 25

Bind only to enzyme containing substrate, decrease Vmax and Km

Question 26

Mechanism based inhibitors

Answer 26

1. Reactive inhibitors are substrate analogs with highly reactive functional groups
2. Transition state analogs
3. Heavy metals that react with amino acid side chains

Question 27

Active site in enzymes

Answer 27

A. Substrates interact with active sites by multiple weak interactions
B. large changes in protein confirmation upon substrate binding
C. Side chain stabilization, coenzymes, metal ions

Question 28

Fructose entrance into glycolysis

Answer 28

Fructose–>fructose-1-P–>DHAP+glyceraldehyde–>glyceraldehyde -3-P

Question 29

Michaelis-Menten equation

Answer 29

vi=Vmax[S]/(Km+[S]

Question 30

Lineweaver-Burk Transformation

Answer 30

x intercept is negative inverse Km while y intercept is inverse Vmax

Question 31

Coenzmyes of TCA

Answer 31

NAD/FAD/CoASh

Question 32

Glutamate Dehydrogenase

Answer 32

Ammonia + alpha keto glutarate –> Glutamate
Forward reaction- reductive amination, GTP down-regulated
Reverse reaction- oxidative deamination, ADP up-regulated