Feedback-resistant Phosphoribosyl-ATP Pyrophosphorylase in L-Histidine-producing Mutants of Corynebacterium glutarnicum
暂无分享,去创建一个
Phosphoribosyl-ATP pyrophosphorylase of two l-histidine-producers of Corynebacterium glutamicum, each selected as a 2-thiazolealanine (TA)-resistant and a 1,2,4-triazole-3-alanine (TRA)-resistant, was found to be 100-fold resistant to l-histidine-inhibition in comparison with wild-type enzyme. It was also resistant to the inhibition by TA, but still as sensitive as the wild-type enzyme to the inhibition by α-methylhistidine. Formation of the pyrophosphorylase in these mutants was not significantly derepressed. However, two-fold derepression was noted with a further improved l-histidine producer KY-10522, a derivative of the above TRA-resistant. KY-10522 is an improved strain in l-histidine-productivity through the additions of resistance markers including increased resistance to TRA. Phosphoribosyl-ATP pyrophosphorylase of KY-10522 was found to be resistant to the feedback inhibition, like it’s parent strain.
[1] Robert G. Martin,et al. [147] Enzymes and intermediates of histidine biosynthesis in Salmonella typhimurium , 1971 .
[2] B. Ames,et al. The Histidine Operon and Its Regulation , 1971 .
[3] V. V. Koningsberger,et al. Regulation of nucleic acid and protein biosynthesis , 1967 .