Zhukov A V, Eremenko V V, Nikolaev A Ia
Mikrobiologiia. 1976;45(4):673-8.
A mutant of Pseudomonas fluorescens, AG-M49, has been isolated, which lacks the ability to synthesize glutamic acid. The mutant contains both aspartase A and aspartase AG. The mutant was characterized by a considerably high activity of glutaminase and aspartase, increasing with the rate flow, during its continuous cultivation on a medium with L-glutamate. L-aspartate penetrates the cells and induces formation of the both deamidases in the mutant. In these conditions, the concentration of exocellular ammonia increases. Asparagine, but not glutamine, also stimulates production of the deamidases in the mutant.
已分离出荧光假单胞菌的一个突变体AG-M49,它缺乏合成谷氨酸的能力。该突变体同时含有天冬氨酸酶A和天冬氨酸酶AG。该突变体的特征在于,在以L-谷氨酸为培养基进行连续培养期间,谷氨酰胺酶和天冬氨酸酶具有相当高的活性,并随流速增加。L-天冬氨酸可穿透细胞并诱导突变体中两种脱酰胺酶的形成。在这些条件下,细胞外氨的浓度会增加。天冬酰胺而非谷氨酰胺也会刺激突变体中脱酰胺酶的产生。