Knight M, Dijkhuizen L, Harder W
Arch Microbiol. 1978 Jan 23;116(1):85-90. doi: 10.1007/BF00408737.
Metabolic control associated with diauxic growth of Pseudomonas oxalaticus in batch cultures on mixtures of formate and oxalate was investigated by measuring intracellular enzyme and coenzyme concentrations and QO2 values during transition experiments from oxalate to formate and vice versa. In transition from oxalate to formate oxalyl-CoA reductase concentration declined after the exhaustion of oxalate and ribulose-1,5-diphosphate carboxylase and 14CO2 fixation appeared upon addition of formate. In the reciprocal transition, ribulose-1,5-diphosphate carboxylase and 14CO2 fixation rate declined sharply after formate exhaustion, and oxalyl-CoA reductase appeared only after addition of oxalate. The intracellular NAD and NADP concentrations measured in the same experiments are reported. At substrate exhaustion the proportion of NAD in the reduced form fell from 15-20% to 2%. On addition of formate to an oxalate-starved culture there was an immediate increase in the proportion of NADH to 50%; such an increase was not observed in the reverse experiment.
通过在从草酸盐到甲酸盐以及反之亦然的转变实验期间测量细胞内酶和辅酶浓度以及QO2值，研究了草酸假单胞菌在甲酸盐和草酸盐混合物的分批培养中与双相生长相关的代谢控制。在从草酸盐到甲酸盐的转变中，草酰辅酶A还原酶浓度在草酸盐耗尽后下降，并且在添加甲酸盐时出现1,5-二磷酸核酮糖羧化酶和14CO2固定。在相反的转变中，1,5-二磷酸核酮糖羧化酶和14CO2固定率在甲酸盐耗尽后急剧下降，并且草酰辅酶A还原酶仅在添加草酸盐后出现。报告了在相同实验中测量的细胞内NAD和NADP浓度。在底物耗尽时，还原形式的NAD比例从15-20%降至2%。向草酸盐饥饿的培养物中添加甲酸盐时，NADH比例立即增加至50%；在反向实验中未观察到这种增加。
