L-lysine epsilon-aminotransferase involved in cephamycin C synthesis in Streptomyces lactamdurans.
In Streptomyces lactamdurans, the precursor of the alpha-aminoadipoyl side-chain of cephamycin C is L-lysine. In this regard, streptomycetes differ strikingly from the fungi, which produce alpha-aminoadipic acid during the synthesis, rather than the breakdown, of L-lysine. Studies using a cell-free system showed that an aminoadipic acid. The product of this reaction was trapped and subsequently purified by ion-exchange chromatography. Thin-layer chromatography, spectrophotometry, and amino acid oxidase digestion studies identified the reaction product as L-1-piperideine-6-carboxylate, implying enzymatic removal of the epsilon amino group of L-lysine. This enzymatic activity (E.C. 2.6.1.36; L-lysine: 2-oxoglutarate 6-aminotransferase) is highly unusual and was previously conclusively demonstrated only in the genus Flavobacterium. In S. lactamdurans, the specific activity of this enzyme reaches a peak early in the fermentation (approximately 20 h) and decreases as the antibiotic begins to appear.
D015074:2-Aminoadipic Acid / Q000096:biosynthesis; D002511:Cephalosporins / Q000096:biosynthesis*; D002513:Cephamycins / Q000096:biosynthesis*; D005285:Fermentation; D008239:Lysine / Q000378:metabolism*; D010875:Pipecolic Acids / Q000032:analysis; D013237:Stereoisomerism; D013302:Streptomyces / Q000201:enzymology / Q000378:metabolism*; D000637:Transaminases / Q000378:metabolism*
D002511:Cephalosporins; D002513:Cephamycins; D010875:Pipecolic Acids; D015074:2-Aminoadipic Acid; D000637:Transaminases; D008239:Lysine