Abstract
L-Alanine:5-keto-octanal aminotransferase has been separated from GOT and GPT activities by DEAE-cellulose chromatography. Two transaminase peaks A and B were observed for γ-coniceine formation and assay showed that these peaks also contained the amino acid:aldehyde aminotransferase (AAT) responsible for aliphatic amine biosynthesis. Kinetic studies showed that γ-coniceine formation with transaminase A had Km for L-alanine and 5-keto-octanal of 27 mM and 1.6 mM respectively. The Vmaxwas 1.3 nkats/mg protein and the activation energy was 3.0 kJ/mol. For transaminase B the Kinm for L-alanine and 5-keto-octanal are 55 mM and 0.14 mM respectively with a Vmaxof 3.3 nkats/mg protein and an activation energy of 0.33 kJ/mol. Transaminase A and B had the same MW and have distinguishable pHmax. γ-Coniceine formation by transaminase A was inhibited uncompetitively by glyoxalate and competitively by pyruvate, whereas with transaminase B uncompetitive inhibition was also observed with glyoxalate; no inhibition was observed with pyruvate which at low concentration (0.25 M) showed slight stimulation of activity.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
