Protein & alcohol metabolism (lecture 31) Flashcards
what is alcohol?
a high energy molecule that can effect metabolism
can oligopeptides be released into the bloodstream?
no
they have to be broken down by amino peptidase first
what happens to macromolecules during starvation?
used for catabolic reactions
to generate heat and energy
proteins are degraded
what happens in catabolism of amino acids?
carbon skeleton is converted to metabolic intermediates
amino group converted to urea by urea cycle
what are transaminases?
key enzymes in amino acid metabolism
swap the amino group for a keto-acid
how is glutamate deaminated?
by glutamate dehydrogenase
produces alpha-ketoglutarate
releases NADH and NH3
reversible reaction
where does the nitrogen in glutamate come from?
plants fix nitrogen from the air and coming it with alpha-ketoglutarate to form glutamate
uses glutamate dehydrogenase
NH4+ + alpha-ketoglutarate = glutamate + H2O
why do people drink alcohol?
binds to GABA receptors
causes relaxation in small amounts
social drug
why is alcohol toxic?
dissolves membranes
depletes NAD stores - acidosis and ketosis
high ration of NADH
• inhibits gluconeogenesis - hypoglycaemia
• inhibits CAC - lipogenesis
headaches come from acetaldehyde - toxic component
acetic acid = vinegar - can be converted back to acetyl CoA
decreases pH of the blood and stops enzymes working
what is steatosis?
fatty liver disease
leads to liver failure
acetic acid causes the liver to swell
what causes alcohol intolerance?
mutation in aldehyde dehydrogenase
levels of acetaldehyde rise
very toxic for the body
flushing, sweating, nausea, liver damage
what converts ethanol to acetaldehyde?
alcohol dehydrogenase
what converts acetaldehyde to acetic acid?
aldehyde dehydrogenase
