The reaction of ornithine aminotransferase with ornithine.
Rat liver ornithine aminotransferase is found to exchange the pro-S hydrogen on the delta-carbon atom of ornithine exclusively, thus showing that the mammalian enzyme transfers the delta-amino group and not the alpha-amino group as has been demonstrated with the plant enzyme [Mestichelli, Gupta & Spenser (1979) J. Biol. Chem. 254, 640-647]. The enzyme also transfers the alpha-amino group of glutamate and the kinetics of the half reactions between the enzyme and both amino acids are compared. Rate and dissociation constants for both reactions are determined.
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D003903:Deuterium; D006207:Half-Life; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D009952:Ornithine / Q000378:metabolism*; D009953:Ornithine-Oxo-Acid Transaminase / Q000378:metabolism*; D011522:Protons; D051381:Rats; D000637:Transaminases / Q000378:metabolism*
D000596:Amino Acids; D011522:Protons; D003903:Deuterium; D009952:Ornithine; D000637:Transaminases; D009953:Ornithine-Oxo-Acid Transaminase