Biochemistry: amino acid catabolism Flashcards
what happens to amino acids if they are not used
they are degraded(no storage)
describe the absorption of amino acids
they are absorbed into intestinal cells and released into blood for absorption by other cells
what is produced by the breakdown of amino acids
produces NH4 and NH3 ions
build up leads to serious problems
what are the major nitrogen excretory molecules (4)
urea, uric acid, creatinine and ammonium ion(NH4)
where does synthesis of urea occur
in the liver
what are the 3 steps in synthesis of urea
transamination, deamination and the urea cycle
what occurs in transamination step of urea synthesis
aminotransferases move amino group from alpha-amino acids to alpha-keto acids
gives glutamate
where does transamination occur
in all tissues
where does deamination and the urea cycle occur
in the liver
after the amino groups are removed what happens to the remaining carbon skeletons
degraded and converted to major metabolic intermediates
converted to glucose or oxidised in TCA cycle
what are ketogenic amino acids degraded to
acetyl-CoA or acetoacetyl-CoA
what can ketogenic amino acids give rise to
ketone bodies or fatty acids
what are glucogenic amino acids degraded to
pyruvate or TCA cycle intermediates
what can glucogenic amino acids be converted to
phosphoenolpyruvate, and then into glucose
