Shuttle mechanism & Regulation Flashcards
Enter the ETC through complex I
Malate aspartate shuttle
Shuttle mechanism
Malate aspartate shuttle
Glycerol phosphate shuttle
Most active NADH shuttle that functions in the LIVER, KIDNEY and heart
Malate aspartate shuttle
Enter the etc through complex II
Glycerol phosphate shuttle
Transfer reducing equivalents from NADH in SKELETAL MUSCLE and BRAIN
Glycerol phosphate shuttle
Shuttle mechanism
Reversible:
Irreversible:
R: malate aspartate
Irre: glycerol phosphate
Number of atp formed in glycolysis
Malate shuttle:
Glycerol shuttle:
M: 8 atp
G: 6 atp
When glucose enters GLYCOLYSIS and undergo KREBS CYCLE
Complete oxidation
Pyruvate must be converted to ___
Oxidize NAD to ____
Acetyl coA
NADH
How many atp if glucose is converted to acetyl coA?
12/14 depends on shuttle system
How many ATP in 1 mol of acetyl coA
12 ATP
2 acetyl coa= _ ATP
24 atp
How many mol of ATP produced if 1mol of glucose undergoes COMPLETE OXIDATION?
36/38 ATP depends on shuttle system
2 types of glycolysis
AEROBIC
ANAEROBIC
Type of glycolysis that forms pyruvate
Aerobic glycolysis
Type of glycolysis that forms lactate, ethanol and CO2
Anaerobic glycolysis
Fermentation of lactate in
Rapidly contracting muscle
Rbc
Fermentation of ethanol in
Yeast
Fates of pyruvate: what enzymes? Product: 1. Lactate 2. Pyruvate 3. Oxaloacetate 4. Ethanol
Enzymes:
- Lactate DH
- Pyruvate DH
- Pyruvate carboxylase
- Pyruvate decarboxylase & alcohol DH
Common mechanism of metabolic regulation
Allosteric regulation
*Covalent modification
Hormonal regulation
Feed back inhibition or feed forward activation
Allosteric regulation
Phosphorylation and dephosphorylation
Covalent modification
Enzyme: HEXOKINASE Found in: Km: Inhibitor: Activator:
Muscle
Low km
Inhibitor: glucose 6-phosphate (allosteric effector)
Activator: glucose
Enzyme: GLUCOKINASE Found in: Km: Inhibitor: Activator:
Liver
High km
Inhibitor: fructose 6 phosphate
Activator: glucose, insulin (hormonal effector) ,
When the glucose in the blood is ⬆️ it will enter the..
Liver
Major regulatory enzyme: PHOSPHOFRUCTOKINASE
Inhibitor:
Activator:
Inhibitor: ATP (allosteric effector) Citrate Activator: AMP ADP Fructose 2,6 bisphosphate
Enzyme: PFK-2
Inhibitor:
Activator:
Regulated by:
I: glucagon
A: insulin
R: hormonal effectors and covalent modification
Enzyme: PYRUVATE KINASE
Inhibitor:
Activator:
I: Atp, Alanine
A: fructose 1,6 bisphosphate, adp
Phosphorylation ( Inactive form)
Dephosphorylation ( active form)
Under hormone control..
Inhibitor:
Activator:
Inhibitor: Glucagon & epinephrine
Activator: insulin
Sugar found in adipose tissue
Fructose
Metabolic intermediate of glycolysis
Glucose 6 phosphate
Mono that can undergo glycolysis by converting it into intermediate
Fructose & galactose