L-LYSINE - ALPHA-KETOGLUTARATE AMINOTRANSFERASE .I. IDENTIFICATION OF A PRODUCT DELTA1-PIPERIDEINE-6-CARBOXYLIC ACID

The product derived from L-lysine was isolated from the L-lysine-α-ketoglutarate aminotransferase system of Flavobacterium fuscum and its properties were studied. Radioactivity from DL-[l-14C]lysine was incorporated exclusively into a product which reacted with o-aminobenzaldehyde. Chromatographic and electrophoretic studies, characterization of the bisulfite and o-aminobenzaldehyde adducts and the condensation product, and comparison with authentic Δ1-piperideine-2-carboxylic acid offer evidence that the product is Δ1-piperideine-β-carboxylic acid. In this aminotransferase reaction, e-amino group of L-lysine is transferred to α-ketoglutarate to yield glutamate and α-aminoadipate-δ-semialdehyde which is immediately converted into the intramolecularly dehydrated form, Δ 1-piperideine-6-carboxylic acid. © 1968, American Chemical Society. All rights reserved.