Metabolic Pathways Flashcards
Glycolysis: where
Cytoplasm
Glycolysis: substrate
Glucose
Glycolysis: end product
Pyruvate/ lactate (also NADH)
Glycolysis: rate limiting step
F6P to F1,6BP E: phosphofructokinase
Hexokinase is inhibited by
G6P
Glucokinase is inhibites by
Fructose 6P
Activates PFK 1
Fructose 2,6 BP
PFK is inhibited by
ATP ad citrate
Shuttle NADH
Malate aspartate shuttle; glycerol phosphate shuttle
Strictly glycolytic organs
RBC, lens, cornea, kidney medulla, testes, WBC
TCA: what for
ATP, gluceneogensis from skeletons of aa, building blocks for aa and heme(succinyk)
TCa: where?
Mitohondria exept succinate dehdrogenase in inner membrane
TCA: substrate
Acetyl coa
TCA: product
CO2, GTP, NADH, FADH2
TCA: rate limiting
Isocitrate to a ketoglutarate(via isocitrate dehydrogenase)
Inhibits citrate to isocitrate step(found in rat poison)
Fluoroacetate
TCA intermediate delivers acetyl coA to cytoplasm for FA synthesis via citrate shuttle
Citrate
TCA intermediate: heme synthesis and activation of ketone bodies
Succinyl coA
TCA intermediate: used for gluconeogensis
Malate
Gluconeogenesis: what for
Glucose from: TCA ang glycolysis intermediates; glycerol; lactate; a ketoacids (glucogenic amino acids)
Gluconeogenesis: where
Liver and kidney; mitochondria and cytoplams
Gluconeogenesis: substrate
Pyruvate
Gluconeogenesis: product
Glucose
Gluconeogenesis: rate limiting step
F1,6BP to F6P (fructose 1,6 bisphosphatase)
All carboxylase require this as a co factor
Biotin
Carboxylase reactions
Pyruvate to OAA(pyruvate carboxylase); acetyl coA to malonyl CoA(acetyl coA carboxylase); propionyl CoA(propionyl CoA)
Fructose 2,6 BP promotes glycolysis and hinders glucneogensis via its action on?
PFK 1- inhibition; F1,6 BP inhibition
Glycogenesis: what for
Synthesis of new glycogen molecules from a-D glucose
Glycogenesis: where
Liver and muscle; cytosok
Glycogenesis: substrates
UDP glucose; ATP and UTP; glycogenin
Glycogenesis: product
Glycogen
Glycogenesis: rate limiting
Glycogen elongation- Glycogen synthase
Glycogenolysis: what for
Produce molecules of a-D- glucose
Glycogenolysis: where
Liver and muscles
Glycogenolysis: substrate
Glycogen; limit dextrin
Glycogenolysis: products
Glucose 1-P and free glcose
Glycogenolysis: rate limiting step
Removal of glucose (breaks a 1-4 bonds) (glycogen phosphorylase)
In what metabolic pahway so you find aldolase A
Glyolysis
In what metabolic pahway so you find aldolase B
Fructose metabolism
Mannose 6-P to fructose 6-P what enzyme?
Phosphomannose isomerase
Glucose to sorbitol is mediated by what enzyme
Aldose reductase
Sorbitol to fructose is mediaed by what enzyme
Sorbitol dehydrogenase
Pentose phosphate pathway: what for
Produces NADPH, ribose 5 phosphate, metabolic use of 5 C sugars
Pentose phosphate pathway: where
Cystoplasm; lipid producing tissues
Pentose phosphate pathway: substrates
Glucose 6-P
Pentose phosphate pathway: products
Ribose 5 P, fructose 6 P, glyceraldehyde 3P, NADPH
Pentose phosphate pathway: rate limiting
Glucose 6 P to 6 phosphogluconate (glucose 6P dehdyrogenase)
Transketolases require what vitamin
Thiamine
Fatty acid synthesis: whatnfir
Palmitate
Fatty acid synthesis: where
Cytosol
Fatty acid synthesis: substrates
1 acetyl coa, 7malonyl co-, NADPH and ATP
Fatty acid synthesis: product
Palmitate
Fatty acid synthesis: rate limiting step
Acetyl coa+ ATP to malonyl CoA (acetyl CoA carboxylase)
Steps in assembly of palmitate
Condensaion, reduction, dehydration, reduction
Ketogenesis: what for?
Converts acetyl coA to ketone bodies
Ketogenesis: where
Mitochondria
Ketogenesis: substrate
Acetyl coA
Ketogenesis: products
Ketone bodied, acetone
Ketogenesis: rate limitig step
Acretoacetyl coA +acetyl coA to HMG coA (HMG CoA synthase)
Why cant the liver degraebprncknvert acetoacetate to CoA
It lacks succinyl coA acetoacetyl CoA transferase (thiophrase)
Cholesterol synthesis: what for
De novo synthesis of cholesterol
Cholesterol synthesis: where
All cells, cytosol and smooth ER; liver and INTESTINES
Cholesterol synthesis: substrates
Acetyl coA, NADPH, ATP
Cholesterol synthesis: products
Lanosterol- cholesterol
Cholesterol synthesis: rate limiting
HMG coA to mevalonate (HMG coA reductase)
Farnesyl pyrophospate is an intemerdiate used for:
(Cholesterol synthesis)
- Synthesis of Coenzyme Q
- Synthesis of dolichol pyrophosphate
- Prenylation of proteins
Bile synthesis: Rate limiting enzyme
Cholesterol 7 a hydroxylase
Bile acids are conjugated with
Glycine and taurine
Excreted bile is reabsorbed where?
Terminal ileum
Steroid hormone synthesis: what for
Glucocorticoids, mineralocorticoids, sex hormones
Steroid hormone synthesis: where
Smooth ER: adrenal cortrex, ovaries and testes, placenta
Steroid hormone synthesis: substrates
Cholesterol, pregnanalone
Steroid hormone synthesis: rate limiting step
Cholesterol to pregnanalone (desmolass)
Blocks rate limiting stepnod steroid formation
Aminogluthemide
Apoprotein secreted by epithelial cells:
B 48
Apoprotein thy actuvates lipoprotein lipase
C II
Apoprotein that mediates uptake by liver
E
Apoprotein secreted by liver
B 100
Apoprotein that activates lecithin cholestrol acyltransferase or LCAT to produce cholesterol esters
A-1
Urea cycle: substrate
NH3, aspartate, CO2
Urea cycle: Rate limiting step
CO2 + NH3 to carbamoyl phosphate (carbamoyl phosphate synthetase I aka CPD I)
Urea cycle: cofactors
N acetylglutamate and Biotin
Cyclic compounds formed by linkage of four pyrrole rings through methyne
Porphyrins
Rate limiting step in heme synthesis
Glycine + succinyl coA to d- aminolevulinic acid (ALA SYNTHASE)
Heme synthesis: cofactor
Pyridoxine
Glycolysis steps
Goodness Gracious father franklin dis go by picking pumpkins
Glycolysis: What
Converts glucose to 3 carbon compounds