Rutgers M, Balk P A, van Dam K
E. C. Slater Institute for Biochemical Research, University of Amsterdam, The Netherlands.
Arch Microbiol. 1990;153(5):478-84. doi: 10.1007/BF00248430.
In chemostat cultures of Klebsiella pneumoniae (K. aerogenes) NCTC 418 we measured the concentrations of glucose and ammonium and we varied the ratio of the (limiting) concentrations of glucose and ammonium in the feed medium. By doing this at different dilution rates we found a range where growth rate varies with either concentration in the culture when the other concentration in the culture is held constant. This proves that within this range, dual-substrate controlled growth occurs. Dual substrate-controlled growth was accompanied by yield coefficients for glucose and for ammonium that were intermediate between the yield coefficients obtained for single glucose or single ammonium limitation. We quantified the control by either substrate in terms of the flux control coefficient with respect to that substrate, where flux refers to growth rate. Dual-substrate controlled growth is reflected by the finding that both flux control coefficients exceed zero, simultaneously. In the transition of glucose to ammonium limitation, the control gradually shifts from glucose to ammonium.
在肺炎克雷伯菌（产气克雷伯菌）NCTC 418的恒化器培养中，我们测量了葡萄糖和铵的浓度，并改变了进料培养基中（限制性）葡萄糖和铵浓度的比例。通过在不同稀释率下进行此操作，我们发现了一个范围，当培养物中的另一种浓度保持恒定时，生长速率会随培养物中任何一种浓度而变化。这证明在该范围内发生双底物控制生长。双底物控制生长伴随着葡萄糖和铵的产率系数，它们介于单一葡萄糖或单一铵限制下获得的产率系数之间。我们根据相对于该底物的通量控制系数来量化任一底物的控制，其中通量指生长速率。双底物控制生长表现为两个通量控制系数同时超过零。在从葡萄糖限制向铵限制的转变过程中，控制逐渐从葡萄糖转移到铵。
