Ackerman Lectures 3 and 4

Question 1

lactate dehydrogenase

Answer 1

reduces pyruvate to lactate, uses NADH as cofactor, replenishes NAD+ (req for glycolysis) (anaerobic cells only)

Question 2

aerobic pyruvate breakdown

Answer 2

oxid decarboxy to CO2 and acetyl coA cat by PDC; 2C acetyl coA then oxid to 2mol CO2 in TCA cycle

Question 3

mito matrix contents

Answer 3

PDC, CAC enz’s, beta oxid enz’s, AA oxid enz’s, DNA, ribosomes, ATP, ADP, Pi, Mg, Ca, K; soluble metab intermeds

Question 4

outer memb

Answer 4

freely permeable to small molecs and ions

Question 5

inner memb

Answer 5

imperm to most small molecs and ions, including H+; has resp e- carriers, ADP-ATP translocase, ATP synthase, other transporters

Question 6

PDH

Answer 6

oxidatively decarboxylates pyruvate to CO2 and acetyl CoA, yields 1 mol NADH per mol pyruvate; E1, E2, E3

Question 7

3 cofactors bd perm to PDH

Answer 7

TPP, lipoic acid, FAD

Question 8

2 cofactors that enter/exit PDH w/each turnover

Answer 8

CoA-SH, NAD+

Question 9

E1

Answer 9

pyruvate DH (TPP)

Question 10

E2

Answer 10

dihydrolipoyl transacetylase (lipoic acid)

Question 11

E3

Answer 11

dihydrolipoyl DH (FAD)

Question 12

PDH products

Answer 12

CO2, then acetyl-coA, then NADH

Question 13

citrate synthase

Answer 13

acetyl-CoA + OAA –> citrate (H2O to CoA-SH); -7.7

Question 14

aconitase

Answer 14

citrate –> cis-aconitate –> isocitrate (lost 2 H2O); +3.2

Question 15

isocitrate dehydrogenase

Answer 15

isocitrate –> a-KG; NAD to NADH + H+; rate limiting step; -2.0

Question 16

a-ketoglutarate dehydrogenase complex

Answer 16

a-KG –> succinyl-CoA; NAD+ to NADH and CoA-SH; -8.0

Question 17

succinyl-CoA synthetase

Answer 17

succinyl-CoA–>succinate; GDP + Pi–>GTP; CoA-SH; NTP synth; -0.7

Question 18

succinate dehydrogenase

Answer 18

succinate–>fumarate (FAD to FADH2); 0

Question 19

fumarase

Answer 19

fumarate–>L-malate (lose OH-); -0.9

Question 20

malate dehydrogenase

Answer 20

L-malate–>OAA (NAD+ to NADH + H+); very unfavorable; +7.1; OAA can’t leave, but malate can

Question 21

TCA inhibition

Answer 21

high E charge; ATP, NADH, acetyl-CoA, FAs

Question 22

TCA stimulators

Answer 22

Ca, AMP, CoA, NAD+, ADP

Question 23

amphibolic

Answer 23

both catabolic and anabolic; produces E and provides metabolites for biosynth of new material

Question 24

anapleurotic

Answer 24

intermeds constantly replenished by metabolite input from other paths

Question 25

catabolic action

Answer 25

NADH, FADH2, GTP (degrad rxns yield high-E metabolites)

Question 26

anabolic action

Answer 26

amino acids (aKG, OAA), FA and cholesterol (acetyl CoA via citrate), porphyrins (succ-CoA), glucose (OAA via malate)

Question 27

carbon sources/feeding steps

Answer 27

AAs (aKG, OAA, succ-CoA, fumarate), odd-chain FA (succ-CoA), pyruvate + CO2 (OAA)