Poole R K, Haddock B A
Biochem J. 1975 Dec;152(3):537-46. doi: 10.1042/bj1520537.
Growth of Escherichia coli K12 in a chemostat was limited by sulphate concentrations lower than 300 muM. The synthesis of extracellular polysaccharide and a change in morphology accompanied sulphate-limited growth. Growth yields with respect to the amount of glycerol or oxygen consumed were sixfold and twofold lower respectively under these conditions than when growth was limited by glycerol. Sulphate-limited cells lacked the proton-translocating oxidoreduction segment of the electron-transport chain between NADH and the cytochromes, and particles prepared from these cells lacked the energy-dependent reduction of NAD+ by succinate, DL-alpha-glycerophosphate or D-lactate, suggesting the loss of site-I phosphorylation. Glycerol-limited cells contained cytochrome b556, b562 and o, ubiquinone and low concentrations of menaquinone. Sulphate limitation resulted in the additional synthesis of cytochromes d, a1, b558 and c550; the amount of ubiquinone was decreased and menaquinone was barely detectable. Non-haem iron and acid-labile sulphide concentrations were twofold lower in electron-transport particles prepared from sulphate-limited cells. Recovery of site-I phosphorylation could not be demonstrated after incubating sulphate-limited cells with or without glycerol, in either the absence or presence of added sulphate. The loss of site-I phosphorylation in sulphate-limited cells is discussed with reference to the accompanying alterations in cytochrome composition of such cells. Schemes are proposed for the functional organization of the respiratory chains of E. coli grown under conditions of glycerol or sulphate limitation.
在恒化器中，大肠杆菌K12的生长受到低于300μM的硫酸盐浓度限制。在硫酸盐限制生长的情况下，伴随着细胞外多糖的合成和形态变化。相对于消耗的甘油或氧气量，在这些条件下的生长产量分别比甘油限制生长时低6倍和2倍。硫酸盐限制的细胞缺乏NADH和细胞色素之间电子传递链的质子转运氧化还原部分，并且从这些细胞制备的颗粒缺乏琥珀酸、DL-α-甘油磷酸或D-乳酸对NAD⁺的能量依赖性还原，这表明位点I磷酸化的丧失。甘油限制的细胞含有细胞色素b556、b562和o、泛醌以及低浓度的甲基萘醌。硫酸盐限制导致细胞色素d、a1、b558和c550的额外合成；泛醌的量减少，甲基萘醌几乎检测不到。从硫酸盐限制的细胞制备的电子传递颗粒中的非血红素铁和酸不稳定硫化物浓度降低了两倍。在有无添加硫酸盐的情况下，将硫酸盐限制的细胞与甘油一起或不与甘油一起孵育后，均未证明位点I磷酸化的恢复。本文参照此类细胞细胞色素组成的伴随变化，讨论了硫酸盐限制细胞中位点I磷酸化的丧失情况。本文还提出了在甘油或硫酸盐限制条件下生长的大肠杆菌呼吸链功能组织的示意图。
