Kinghorn J R, Pateman J A
J Bacteriol. 1976 Jan;125(1):42-7. doi: 10.1128/jb.125.1.42-47.1976.
Ten mutants of Aspergillus nidulans lacking nicotinamide adenine dinucleotide-specific glutamate dehydrogenase (NAD-GDH) have been isolated, and their mutations (gdhB1 through gdhB10) have been shown to lie in the gdhB gene. In addition, a temperature-sensitive gdhB mutant (gdhB11) has been isolated. A revertant (designated R-5) of the mutant gdhB1 bears an additional lesion in the gdhB gene and has altered NAD-GDH activity with altered Km values for ammonia or ammonium ions and for alpha-ketoglutarate. These results suggest that gdhB specifies a structural component for NAD-GDH. The growth characteristics of gdhB mutants indicate the routes by which amino acids are utilized as nitrogen and carbon energy sources. The properties are described of the double mutants bearing the mutations gdhB1 and gdhA1 or tamA119, which have low NADP-GDH activity.
已分离出10株缺乏烟酰胺腺嘌呤二核苷酸特异性谷氨酸脱氢酶(NAD-GDH)的构巢曲霉突变体,并且已证明它们的突变(gdhB1至gdhB10)位于gdhB基因中。此外,还分离出了一个温度敏感型gdhB突变体(gdhB11)。突变体gdhB1的一个回复体(命名为R-5)在gdhB基因中有另外一个损伤,并且其NAD-GDH活性发生了改变,对氨或铵离子以及对α-酮戊二酸的Km值也发生了改变。这些结果表明,gdhB指定了NAD-GDH的一个结构成分。gdhB突变体的生长特性表明了氨基酸作为氮源和碳能源被利用的途径。描述了带有gdhB1和gdhA1或tamA119突变的双突变体的特性,这些双突变体具有低NADP-GDH活性。