LIPID METABOLISM 2 Flashcards
_____________ is 90% of dietary lipids
emulsified by
triacylglycerol
bile
fatty acid synthesis and oxidation are reciprocally regulated
___________ state: storage is favored
fed state
fatty acid synthesis and oxidation are reciprocally regulated
___________ state: FA oxidation is favored as fats serve as fuel in place of glucose
fasting state
TAGs are stored in _________
adipocytes
____________ lipase hydrolyses TAG to free fatty acids and glycerol
hormone sensitive lipase
at low carbohydrate and insulin concentrations, TG hydrolysis is stimulated by increased ___________
epinephrine
in storage and mobilization of fatty acids and adipocytes
epinephrine will bind to _____________ receptor and will activate __________
beta adrenergic receptor
protein kinase A
fatty acid oxidation occurs mainly in the _______ and _______
liver and skeletal muscles
active form of fatty acid
fatty acid acyl co-A
in cytosol, FA are activated by esterification to CoAsh by _________
net of ______ ATPs are consumed
acyl-coA synthetase
2
4 steps of beta oxidation in the mitochondrial matrix
oxidation
hydration
oxidation
cleavage/thiolysis
beta oxidation in the mitochondrial matrix
1st step oxidation of the ________
removal of _________- by FAD to FADH2
enzyme: _______________
product: ____________
beta carbon
hydrogen
Acyl coA dehydrogenase
trans unsaturated enoyl CoA
beta oxidation in the mitochondrial matrix
2nd step is incorporation of H20
enzyme _______
product _______
enoyl coa hydratase
3,-hydroxyacyl COA
beta oxidation in the mitochondrial matrix
3rd step hydrogen is removed
enzyme: _______________
product: ______________
enzyme: 3-L hydroxyacyl CoA dehydrogenase
product: beta ketoacyl CoA
beta oxidation in the mitochondrial matrix
4th step cleavage between alpha and beta carbon with the help of CoAsh
enzyme: ______________
product: ______________
enzyme: acyl-CoA acetyltransferase/ thiolase
product: fatty acyl CoA + Acetyl CoA
most of acetyl-CoA from beta oxidation enters krebs
however some form ketone bodies such as __________, ________, and ________-
acetoacetate
beta hydroxybutyrate
acetone
control points for FA oxidation
fed state: insuline levels _______
increases
insuline stimulates formation of ________ which inhibits meow
Malonyl CoA
CAT 1
control points for FA oxidation
fasted state: ______ and ________
glucagon inactivates _________ synthesis enzyme
malonyl CoA
two main enzymes of fatty acid synthesis
fatty acid synthase
acetyl CoA carboxylase
coenzymes and cofactors of fatty acid synthesis
biotin, NADPH, magnesium, manganese
catalyzes first and committed step of FA synthesis
________ dependent
acetyl-coa carboxylase
biotin
acetyl coa carboxylase is hormonally regulated by ________ and _______ which stimulates _________ of enzyme
glucagon and epinephrine
phosphorylation
