lecture 3 Flashcards
Compare and Contrast FAS and oxidation
oxidation: occurs in mitochondria, coenzyme A used instead of acyl carrier, FAD and NAD+ are generated instead of NADPH, oxidation goes from carboxyl to methyl, FAS enzymes are in a single multi enzyme complex
How do lipid droplets differ from mixed micelles?
mixed micelles have a monolayer of phospholipids and bile salts, are associated with lipases, and their cores have dietary fats, cholesterol and dietary lipids
what are the characteristics of the lipids in the core of lipoproteins
TAG and cholesterol esters
What are the steps of FA oxidation?
oxidation
hydration
oxidation
thiolysis
How are carboxylates activated? What enzyme is used?
via long chain acyl-coA synthase
How are FA transported into the mitochondria?
via carnitine palmitoyl transferase 1 and transloacase
How does LPL work?
binds apocII and bites off fatty acids
what do VLDLs transport?
cholesterol from liver to body tissue
what apolipoproteins are in chylomicrons?
B48, C and E
what apolipoproteins are in VLDL
B100, C, E
Why are HDLs the most dense?
HDLs are the most dense because they are the most protein rich and have the least amount of TG
How are fatty acids released from chylomicrons
chylomicron binds GPI on caveolae on vascular epithelial cell
cell surface recognizes and binds to apoE
apoCII triggers activation of lipoprotein lipase, which breaks off fatty acid from lipoprotein lipase
outside cells: apoB48 triggers release of VLDL remnants/chylomicrons
How are fats mobilized
glucagon is released and binds to GPCR, Atp makes cAMP and activates pKa, aka phosphorylates perlipin, perilipin makes gap on lipid droplet surface, pka phosphorylates hormone sensitive lipase, which goes to lipid droplet and releases free fatty acids
What enzyme does unsaturated fatty acid oxidation used
enoyl coA isomerase
what enzyme do odd chain fatty acids
propionyl coA carboxylase(biotin)
and methylmalonyl coA mutase
