Term
| Problem with doing glycolysis in the liver |
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Definition
| ATP inhibits PK and PFK, and the ATP/ADP ratio does not change much in the liver |
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Term
| Role of Fructose 2,6 bisphosphate |
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Definition
| overrides the inhibition on PFK-1 |
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Term
| Domains of F-2,6 bisphosphatase |
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Definition
- PFK-2 (add phosphate to two position)
- biphosphatase (remove phosphate from 2 position)
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Term
| How is F2,6 biP controlled |
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Definition
- if dephosphorylated, PFK-2 is functional (very active if insulin present- remember, insulin dephosphorylates substances)
- if phosphorylated, phosphatase is functional
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Term
| How do we overcome negative influence of ATP on PK? |
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Definition
| build up of F 1,6 phosphate overides ATP levels |
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Term
| Process of making cytosolic acetyl CoA |
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Definition
- start by combining acetyl CoA and OAA to make citrate via citrate synthase
- make isocitrate, IDH will be inhibit
- allows for isocitrate to go back to make citrate (cause build up of citrate)
- via transporter, citrate goes into cytosol
- citrate hydrolyzed to make OAA and acetyl-CoA via citrate lyase
- acetyl-CoA goes into FA synthesis
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Term
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Definition
- OAA and NADH make NAD and malate via malate DH
- allows us to keep running glycolysis (produce NAD)
- take malate and NADP and create CO2, pyruvate, and NADPH via malic enzyme
- pyruvate goes back into matrix via transporter to be converted to acetyl CoA via PDH
- pyruvate could also be converted to OAA in matrix via pyruvate carboxylase (if acetyl CoA builds up)
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Term
| Purpose of pentose phosphate shunt pathway |
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Definition
| regnerate NADPH needed for fatty acid synthesis |
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Term
| Two different pathways of pentose phsophate pathway/ hexose monophopshate pathway (HMP) |
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Definition
- oxidative pathway to generate NADPH (irreversible path)
- non-oxidative pathway to generate ribose-5 phosphate for nucleotide biosynthesis (freely reversible)
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Term
| Process of oxidative pathway of pentose phosphate pathway |
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Definition
- G6P and NADP form NADPH and 6PG lactone via G6P dehydrogenase
- reacts with glucose in ring form and oxidizes anomeric carbon
- 6PG lactone turned into linear form: 6PG via lactonase
- 6PG and NADP create NADPH, CO2, and ribulose 5-phosphate via 6PG DH
- controlled by cytosolic NADPH/NADP ratio
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Term
| Location of pentose phosphate pathway |
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Definition
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Term
| Process of nonoxidative pathway of pentose phosphate pathway |
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Definition
- two F6P and G3P creates three ribulose 5 phosphate via transketolase, followed by transaldolase, followed by another transketolase
- transketolase requires thiamine pyrophosphate
- three ribulose 5 phosphate to three ribose 5 phosphate via isomerase
- used for nucleotide biosynthesis
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Term
| Explain what is ment by non-oxid path of HMP pathhway can be used as a salvage pathway |
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Definition
| used to convert excess ribulose 5 phosphate generated by oxidative path back to intermediates of glycolytic path |
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Term
| How do we elongate palmitate in liver |
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Definition
| via elongase, we use malonyl CoA as a donor of two carbones and NADPH as the reducing agent and follow the same pattern we used to make palmitate: reduction, remove water, reduction |
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Term
| Describe process of synthesis of oleyl CoA |
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Definition
- palmityl CoA and malonyl CoA create CO2, CoA, and stearyl CoA via elongase
- stearyl CoA, oxygen, and 2 cyc b5 (ferrous) create 2 waters, 2 cyc 5 (ferric), and oleyl-CoA via fatty acyl-CoA desaturase
- regenerate ferric form of cyc 5 using cyc b5 reductase (coenzyme; FAD) and using NADPH as our reducing agent
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Term
| Cellular location of monooxygenases that insert double bonds |
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Definition
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Term
| How do we control movement of fatty acids into matrix |
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Definition
| malonyl CoA is a negative inhibitor of the fatty acyl-CoA carnitine transferase I |
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Term
| Process to synthesize TAG's |
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Definition
- alpha glycerol phosphate and 2 fatty acyl-CoA's converted to 2 CoA's and phosphatidate via acyl-CoA transferase
- phosphatidate converted to inorganic phosphate and DAG via phosphatidine phosphatase
- DAG and fatty acyl CoA converted to TAG and CoA via acyl-CoA transferase
- TAG packaged with cholesterol, apo B100, and phospholipids into VLDL's which are released into the blood
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Term
| Cellular location of synthesis of TAG |
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Definition
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Term
| Sources of glycerol 3 phosphate |
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Definition
- DHAP and NADH create NAD and alpha glycerol phosphate via alpha glycerol phosphate dehydrogenase
- glycerol and ATP converted to alpha glycerol phosphate and ADP via glycerokinase
- only found in the liver (liver is the only one with enzyme)
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