Higa A I, Milrad de Forchetti S R, Cazzulo J J
J Gen Microbiol. 1976 Mar;93(1):69-74. doi: 10.1099/00221287-93-1-69.
Pseudomonas fluorescens grown on glucose or glutamate at 1 or 20 degrees C, or on acetate at 20 degrees C, as sole carbon sources, contained both pyruvate carboxylase and phosphoenolpyruvate carboxylase. Pyruvate carboxylase was insensitive to acetyl-coenzyme A and L-aspartate, and its level in cell-free extracts was markedly dependent on the carbon source for growth, the highest specific activity being attained in glucose-grown cells. Phosphoenolpyruvate carboxylase, on the other hand, although less dependent on the nature of the carbon source,showed its highest level in acetate-grown cells; the enzyme activity required acetyl-coenzyme A and was strongly inhibited by L-aspartate. The micro-organism had, in addition, a phosphoenolpyruvate carboxykinase, which showed its highest specific activity in cells grown on acetate, and a NADP-linked malate enzyme, apparently repressed by acetate and showing its highest specific activity in glutamate-grown cells.
荧光假单胞菌在1℃或20℃以葡萄糖或谷氨酸为唯一碳源生长，或在20℃以乙酸盐为唯一碳源生长时，同时含有丙酮酸羧化酶和磷酸烯醇式丙酮酸羧化酶。丙酮酸羧化酶对乙酰辅酶A和L-天冬氨酸不敏感，其在无细胞提取物中的水平明显取决于生长的碳源，在以葡萄糖生长的细胞中达到最高比活性。另一方面，磷酸烯醇式丙酮酸羧化酶虽然对碳源性质的依赖性较小，但在以乙酸盐生长的细胞中水平最高；该酶活性需要乙酰辅酶A，并受到L-天冬氨酸的强烈抑制。此外，该微生物还有一种磷酸烯醇式丙酮酸羧激酶，其在以乙酸盐生长的细胞中比活性最高，以及一种NADP连接的苹果酸酶，显然受到乙酸盐的抑制，在以谷氨酸生长的细胞中比活性最高。
