Hayashi Mikiro, Ohnishi Junko, Mitsuhashi Satoshi, Yonetani Yoshiyuki, Hashimoto Shin-Ichi, Ikeda Masato
Biofrontier Laboratories, Kyowa Hakko Kogyo Co., Ltd., Tokyo, Japan.
Biosci Biotechnol Biochem. 2006 Feb;70(2):546-50. doi: 10.1271/bbb.70.546.
Toward the elucidation of advanced mechanisms of L-lysine production by Corynebacterium glutamicum, a highly developed industrial strain B-6 was analyzed from the viewpoint of gene expression. Northern blot analysis showed that the lysC gene encoding aspartokinase, the key enzyme of L-lysine biosynthesis, was up-regulated by several folds in strain B-6, while no repression mechanism exists in L-lysine biosynthesis of this bacterium. To analyze the underlying mechanisms of the up-regulation, we compared the transcriptome between strain B-6 and its parental wild-type, finding that not only lysC but also many other amino acid-biosynthetic genes were up-regulated in the producer. These results suggest that a certain global regulatory mechanism is involved in the industrial levels of L-lysine production.
为了阐明谷氨酸棒杆菌生产L-赖氨酸的先进机制，从基因表达的角度对高度发达的工业菌株B-6进行了分析。Northern印迹分析表明，编码天冬氨酸激酶（L-赖氨酸生物合成的关键酶）的lysC基因在菌株B-6中上调了几倍，而该细菌的L-赖氨酸生物合成中不存在抑制机制。为了分析上调的潜在机制，我们比较了菌株B-6与其亲本野生型之间的转录组，发现不仅lysC而且许多其他氨基酸生物合成基因在生产菌株中都上调了。这些结果表明，某种全局调控机制参与了L-赖氨酸的工业生产水平。
