metabolismo de los aminoácidos Flashcards
aminotransferase tests usually carried out to asses tissue damage in the body ?
**alanine –> pyruvate
glutamate –> alpha-ketoglutarate
aspartate –> oxaloacetate
1# glutamate- pyruvate –> alanine + alpha-ketoglutarate (alanine aminotransferase)
2# glutamate - oxaloacetate –> aspartate + alphaketoglutarate (aspartate aminotransferase)
how is ammonia collected in glutamate removed in the mitochondria ?
enzymes involved ?
activators ? inhibitors ?
enzymes: transaminase and glutamate dehydrogenase
transdeamination happens in two steps:
1# transaminase that takes an amino group from an amino acid that becomes an alpha keto acid and gives the amino to alpha ketoglutarate that becomes glutamate
2#glutamate is then oxidized via glutamate dehydrogenase (uses NAD+ or NADP+) and then turns into the keto form via water molecule into alpha-ketoglutarate, releasing ammonia which is processed into urea for excretion.
inhibited by GTP (a sign of plenty of energy –> no need to break down protein mass)
how to get rid of toxic ammonia in the blood ?
how does the “carrier substance” deal with it ?
Excess ammonia in extrahepatic tissues is added to glutamate to form glutamine (non-toxic), a process catalyzed by glutamine synthetase (requires ATP).
alternative to the formation of glutamine via the glutamine synthetase reaction in the muscle ?
it is possible instead to transfer the amino group of glutamate to pyruvate, using alanine aminotransferase.
glucose-alanine cycle.
Urea cycle ?
regulatory step ?
location ?
two ammonia acquiring rxns ?
stoichimoetry ?
see lecture
how to diagnose genetic defects in the urea cycle ?
see
GENETIC DEFECTS IN THE UREA CYCLE ENZYMES AND POSSIBLE TREATMENTS ?
more “specific treatment” ? how do you treat N-acetyl glutamate synthetase deficiency ?
see
ketogenic Vs. glucogenic amino acids ?
see
cofactors involved in amino acid catabolism ?
see
