Biochem Lecture 15

Front 1

What are the 4 fates of UDP-Glucose?

Back 1

1) UDP-Glucuronic Acid

2) Glycogen

3) Glycoproteins, Polysaccharides, Gal Metab.

4) Glucose 1 P

Front 2

What is the net anaerobic glucose reaction?

Back 2

Glucose + 2P + 2ADP --> 2 Lactate + 2ATP + 2H20

Front 3

What is the net aerobic glycolysis reaction?

Back 3

Glucose + 2P + 2ADP +2NAD --> 2 Pyruvate +2ATP +2NADH + 2H+ +2H20

Front 4

What is the investment phase of glycolysis?

Back 4

Glucose --> G6P (requires ATP) --> F6P --> F1,6BP (requires ATP)

-need to put in 2 ATP

Front 5

Why do we use F16BP instead of G16BP?

Back 5

Because we want to get symmetric products (two 3 carbon molecules)

Front 6

What is the second phase of glycolysis? How much ATP does it produce?

Back 6

G3P & DHAP --> 13BPG --> 3PG (generates ATP) --> 2PG --> P-enolpyruvate --> Pyruvate (generates ATP)

-4 ATP made

Front 7

Red cells lack _______, so they depend on ______ for ATP production?

Back 7

-mitochondria

-glycolysis

Front 8

A woman with unstable red blood cells & anemia has a problem with what?

Back 8

glycolysis

Front 9

How does glycolysis provide energy for exercise?

Back 9

-starts with ATP already present --> uses anaerobic glycolysis (2 mins) --> uses aerobic glycolysis + TCA

Front 10

What are the 3 fates of G6P?

Back 10

1) Pentose 5-Phosphate (nucleotides & NADPH)

2) Pyruvate (can go to lactate)

3) Glycogen

Front 11

Dihydroxyacetone phosphate provides intermediates for ________ synthesis

Back 11

lipid

Front 12

Dihydroxyacetone phosphate can be converted to phosphatidic acid which is a precursor to ______ & ______

Back 12

-triacylglycerol

-phospholipids

Front 13

1,3 BPG generates _________, which regulates hemoglobin. Which enzyme does this conversion?

Back 13

-2,3 BPG
-bisphosphoglycerate mutase

Front 14

We can generate ______ from 3 phosphoglycerate?

Back 14

Serine (amino acids)

Front 15

What does G3P dehydrogenase catalyze? What does it require?

Back 15

-G3P --> 1,3BPG

-requires P & NAD+

Front 16

What does arsenic do?

Back 16

Targets G3P dehydrogenase and pretends to be phosphate

Front 17

How do we regenerate NAD+ back from G3P dehydrogenase reaction under anaerobic conditions?

Back 17

-Conversion of Pyruvate --> Lactate by LDH

Front 18

G3P dehydrogenase shows ______ cooperativity. What does this mean?

Back 18

-negative

-means enzyme is less sensitive to changes in substrate concentration --> always wants to do glycolysis

Front 19

What do oxidizing reactions use ____ and reduce it to _____ to oxidize the substrate

Back 19

NAD+

NADH

Front 20

Is there more NAD+ or NADH in the cell?

Back 20

NAD+ because that is the form it gets used

Front 21

Pellagra

Back 21

-Selective deficiency of niacin (nicotinic acid)

-NAD formed from niacin (member of VItamin B familiy)

-D cubed --> Dimentia, Dirreah, Dermetitis

Front 22

The regulation of glycolysis occurs at steps that are far from _______

Back 22

equilibrium

Front 23

Which enzymes are regulated (irreversible) in glycolysis & what regulates them?

Back 23

1) hexokinase (neg: G6P)

2) PFK-1 (pos: AMP, neg: ATP & citrate)

3) Pyruvate Kinase (pos: F16BP)

Front 24

What is the key regulatory enzyme/step in glycolysis?

Back 24

F6P --> F16BP by PFK-1

Front 25

Under resting conditions, PFK-1 is strongly _________

Back 25

inhibited

Front 26

Rate of PFK-1 is determined by amount of ___________ (pos. regulator), especially in liver

Back 26

Fructose-2,6-Bisphosphate

Front 27

Fructose-2,6-Bisphosphate is made from ________ by ________

Back 27

-F6P

-PFK-II

Front 28

Which phosphatases change F26BP & F16BP back to F6P?

Back 28

-Phosphatase I & Phosphatase II

Front 29

How is PFK2 regulated by insulin?

Back 29

-when PFK2 phosphorylated it goes from kinase --> phosphatase which changes F26BP --> F6P: TURNS OFF PK1

-Insulin activates phosphatase to take phosphate off of PFK2 --> turns it back into kinase --> makes F6P into F26BP: TURNS ON PFK1

Front 30

Deficiencies in glycolysis mainly affect _____ & _______

Back 30

-red cells

-skeletal muscle

Front 31

Pyruvate can be made into lactate, go into TCA or be made into _______

Back 31

amino acids

Front 32

2-Deoxyglucose affects _________ by generating neg. feedback inhibition

Back 32

hexokinase

Front 33

Fluroide inhibits _______

Back 33

Enolase

Front 34

________ is the most common enzyme defect in glycolysis

Back 34

Pyruvate Kinase

Front 35

How come pyruvate kinase can be defective in red blood cells & normal in other tissues?

Back 35

-PK comes in 4 isoenzymes: M1, M2, L & R

Front 36

Patient has defect in Muscle PFK1, why do they not have anemia?

Back 36

Because there are 3 PFK enzymes --> Red cells have mix of the 3, so they're ok