protein_metabolism
protein metabolism
see also:
basic overview
- proteins conjugated with ubiquitin are destined for degradation
- dietary amino acids and the amino acids that form from catabolism of protein form an amino acid pool
- the fate of these amino acids may take several routes:
- urinary excretion (although most filtered AA's are reabsorbed)
- formation of body protein (some of which is lost as hair, urinary protein, stools, etc)
- formation of hormones, neurotransmitters
- formation of creatine ⇒ phosphyrylcreatine in muscle ⇒ creatinine ⇒ renal excretion
- metabolism to purines & pyrimidines ⇒ RNA & DNA
- excess pyrimidines ⇒ CO2 + NH3 ⇒ urea
- excess purines ⇒ uric acid
- transamination or amination to other AA's
- oxidative deamination in liver:
- ketogenic AA's (leucine, isoleucine, phenylalanine, tyrosine) ⇒ acetoacetate + NH4+ ⇒ urea
- glucogenic AA's (alanine et al ) ⇒ glucose + NH4+ ⇒ urea
- in addition, sulphur containing AA's (ie. cysteine, methionine) are the source of urinary sulphates
protein_metabolism.txt · Last modified: 2009/01/30 04:54 by 127.0.0.1