title: Lysine degradation in Candida. Characterization and probable role of L-norleucine-leucine, 4-aminobutyrate and delta-aminovalerate:2-oxoglutarate aminotransferases.
abstract: Three enzymes partially purified that catalyze respectively the transamination of L-norleucine, 4-aminobutyrate and delta-aminovalerate with alpha-ketoglutarate as aminoacceptor were characterized and isolated from L-lysine adapted cell of Candida guilliermondii var. membranaefaciens. The transaminases have a maximum activity in the pH range of 7.8-8.5 and at 55 degrees C, 45 degrees C and 40 degrees C respectively. alpha-Ketoglutarate and to a lesser extent pyridoxal-5'-phosphate were effective protecting agents against rise in temperature. The enzymes exhibit absorption maximum at 280 nm, 330 nm and 410 nm. The fact that L-norleucine-leucine aminotransferase, 4-aminobutyrate aminotransferase and delta-aminovalerate aminotransferase are strongly induced by growing the yeast Candida on L-lysine suggests new hypothetic pathways for the catabolism of L-lysine where the main substrate of each aminotransferase could be an intermediary metabolite.
authors.affiliation: Laboratoire d'Enzymologie, Université Pierre et Marie Curie, UER 58, Paris, France.
authors.forename: P A
authors.initials: PA
authors.lastname: Der Garabedian
authors.forename: J J
authors.initials: JJ
authors.lastname: Vermeersch
mesh_terms: D000612:4-Aminobutyrate Transaminase / Q000378:metabolism; D002175:Candida / Q000187:drug effects / Q000201:enzymology*; D004790:Enzyme Induction; D006863:Hydrogen-Ion Concentration; D008239:Lysine / Q000378:metabolism* / Q000494:pharmacology; D013379:Substrate Specificity; D013696:Temperature; D000637:Transaminases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D000637:Transaminases; D000612:4-Aminobutyrate Transaminase; C050903:5-aminovalerate aminotransferase; C053548:2-aminohexanoate transaminase; D008239:Lysine