Production of L-lysine by alanine auxotrophs derived from AEC resistant mutant of Brevibacterium lactofermentum

• Published in: Agricultural and biological chemistry Vol. 42; no. 9; pp. 1773 - 1778
• Main Authors: Tosaka, O, Hirakawa, H, Yoshihara, Y, Takinami, K, Hirose, Y. (Ajinomoto Co. Inc., Kawasaki, Kanagawa (Japan). Central Research Labs.)
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 01.09.1978
• ISSN: 0002-1369
• DOI: 10.1080/00021369.1978.10863244

Relationships between L-lysine productivity and the formation of alanine in Brevibacterium lactofermentum were investigated. Alanine can be formed from pyruvate by transaminase with L-amino acid, and directly from aspartate in the presence of a-ketoglutarate and L-leucine. The later suggests that aspartate β-decarboxylase may contribute to the formation of L-alanine. However, this activity is approximately l/20~l/50 of transaminase activity. Productivity of L-lysine was inversely as the level of pyruvate-L-amino acid transaminase. It was cofirmed by the derivation of alanine auxotrophs from AJ3445 (AEC r ). The best L-lysine producer, AJ3799, accumulated 39 mg/ml of L-lysine and lacked pyruvate-L-amino acid transaminase.