Kinghorn J R, Pateman J A
J Gen Microbiol. 1975 Feb;86(2):294-300. doi: 10.1099/00221287-86-2-294.
A total of 41 mutants lacking NADP L-glutamate dehydrogenase (NADP-GDH) activity have been studied. All the mutations were located at the gdhA locus within 0-1% recombination of gdhAI. Two mutants, gdhAI and gdhA2, out of five examined, produced cross-reacting material which neutralized NADP-GDH anti-serum. The mutant gdhA9 has altered Km values for all five substrates: ammonium, alpha-ketoglutarate, l-glutamate, NADPH and NADP. The mutant gdhA20 had temperature-sensitive growth, abnormal ammonium-regulation characteristics and thermolabile NADP-GDH activity. These results show that gdhA is the structural gene for NADP-GDH.
总共对41个缺乏NADP-L-谷氨酸脱氢酶(NADP-GDH)活性的突变体进行了研究。所有突变均位于gdhA基因座,与gdhAI的重组率在0-1%以内。在检测的5个突变体中,有两个突变体gdhAI和gdhA2产生了能中和NADP-GDH抗血清的交叉反应物质。突变体gdhA9对所有五种底物(铵、α-酮戊二酸、L-谷氨酸、NADPH和NADP)的米氏常数(Km值)都发生了改变。突变体gdhA20具有温度敏感型生长、异常的铵调节特性以及热不稳定的NADP-GDH活性。这些结果表明,gdhA是NADP-GDH的结构基因。