BIOCHEM Flashcards
Glycolysis Rate Limiting Enzyme
PFK 1
Glycogenesis Rate Limiting Enzyme
Glycogensynthase
Glycogenolysis Rate Limiting Enzyme
Glycogen Phosphorylase
Gluconeogenesis Rate Limiting Enzyme
Fructose 1-6 bisphosphate
PPP Rate Limiting Enzyme
Glucose 6 phosphate dehydrogenase
Citric Acid Cycle- Krebs- TCA Cycle Location & Main Function
Mito matrix. Purpose: Oxidation of acetyl CoA to CO2 and water. Produces NADH and FADH2.
* Doesnt require O2 but wont occur anaerobically because NADH and FADH2 will inhibit
Acetyl Co-A
Contains High energy thioester bond used to drive other rxns upon hydrolysis
Pyruvate dehydrogenase complex location and enzymes
Mitochondrial Matrix
1- Conversion of pyruvate to acetyl coA ( pyruvate dehydrogenase, dihydropropyl transacetylase, dihydrolipoyl dehydrogenase)
2 Regualtion of PDH ( pyruvate dehydrogenase kinase and pyruvate dehydrogenase phosphatase)
In the PDH complex, PDH oxidizes ___ to create CO2. it Requires ___ and ____
Pyruvate TPP and Mg2+
In the PDH complex, dihydropropyl transacetylase oxidizes ____ using lipoic acid. It transfers the resulting acetyl group to coA
remaining two c molecule
In the PDH complex, dihydrolipoyl dehydrogenase uses ____ to reoxidize lipoic acid forming ______ which can later transfer e- to NAD+ , forming NADH that can go into ETC
FAD, FAD2
PDH complex:
PDH kinase phosphorylates PDH when ___ and ___ are high to turn it off.
ATP or Acetyl CoA
PDH complex:
PDH phosphatase dephosphorylates PDH when ____ is high to turn it on
ADP
5 Ways Acetyl CoA can be produced
Glycolysis- PDH complex Fatty acid oxidation (beta oxidation) Amino Acid Catabolism Ketones Alcohol
Glycolysis:
Glucose —-> Glucose 6 Phosphate
Enzyme: Hexokinase ( in peripheral tissue) Glucokinase (in liver, insulin responsive). ATP consumed. Mg2 cofactor, Irreversible (traps glucose in the cell)
Glycolysis:
Glucose 6P—-> Fructose 6-P
Isomerase
Glycolysis:
Fructose 6P—–> Fructose 2,6 Bisphosphate
PFK 2. Insulin up regulates and Glucagon decreases. PFK 2 stimulates PFK1 and ATP is consumed
Glycolysis:
Fructose 6P—-> Fructose 1,6 Bisphosphate
PFK-1 (upregulated by PFK2 and AMP). Downregulated by ATP and Citrate. ATP is consumed, irreversible and RATE LIMITING STEP
Glycolysis
Fructose 1,6 Bisphosphate —> x2
Either Glyceraldehyde 3-P or Dihydroxyacetone - P (DHAP)
Glycolysis:
Glyceraldehyde 3-P —-> 1,3 Bisphosphoglycerate
Glyceraldehyde 3- Phosphate dehydrogenase, adds a phosphate, catalyses oxidation. NAD+ is reduced to NADH which can then go into ETC if oxygen is present
Glycolysis :
1,3 Bisphosphoglycerate —-> 2,3 Bisphosphoglycerate
Occurs in the Red blood cells. Enzyme is bisphosphoglycerate mutase.. a mutase can move one functional group from 1 position to another. The net here is 2 ATP/ glucose. RBC have anaerobic glycolysis only, no mitochondria. HBA = decreasing affinity for o2 and unloading in tissues
Glycolysis:
1,3 Bisphosphoglycerate—-> 3 Phosphoglycerate
3 PK (3 phosphoglycerate kinase) * ATP is produced and example of substrate level phosphorylation (not o2 dependent)
Glycolysis:
SUbstrate level phosphorylation enzyme
3 phosphoglycerate kinase and pyruvate kinase
Glycolysis:
3 phosphoglycerate —-> 2 phosphoglycerate
Mutase
Glycolysis
2 phosphoglycerate —-> PEP
Enolase
Glycolysis:
PEP—–> Pyruvate
Pyruvate kinase is enzyme. Activated by Fructose 1,6 BP. ATP and substrate level phosphorylation. Irreversible
Glycolysis:
DHAP- dihydroxyacetone phosphate
Used in hepatic and adipose tissue for triacylglycerol synthesis, formed from F 1,6 BP, Can be isomerized to glycerol 3-P to be converted to glycerol
3 Irreverible enzymes of Glycolysis
Gluco/hexokinase,
PFK
Pyruvate kinase
During glycolysis, if oxygen or mitochondria are absent NADH is oxidized by
Lactate dehydrogenase
Physiological changes that promote right shift of oxygen dissociation curve
Increased 2,3 BPG, low pH, Exercise, High pCO2.
Three traits of amino acids
Non polar, non aromatic, non polar
