Effects of carbonylcyanide-m-chlorophenylhydrazone (CCCP) and acetate on Escherichia coli O157:H7 and K-12: Uncoupling versus anion accumulation
Effects of carbonylcyanide-m-chlorophenylhydrazone (CCCP) and acetate on Escherichia coli O157:H7 and K-12: Uncoupling versus anion accumulation
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DOI：
10.1111/j.1574-6968.1997.tb10396.x
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发表时间：
1997-06-01
影响因子：
2.1
通讯作者：
Russell, JB
中科院分区：
文献类型：
--
作者：
DiezGonzalez, F;Russell, JB
在pH 6.5的磷酸钠缓冲液中厌氧培养的大肠杆菌O 157：H7和K-12的非生长细胞以约8 μ mol的速率消耗葡萄糖。(mg蛋白质）（-1）.h（-1），细胞内pK值分别为7.3和7.5。解偶联剂，羰基氰-间氯苯腙（CCCP），引起细胞内的pH值，ATP和钾的两种菌株的显着下降。低浓度的CCCP刺激葡萄糖消耗速率，但高浓度的抑制。乙酸盐也引起细胞内pH值的降低，但它从未引起葡萄糖消耗速率的大幅降低。乙酸使E. coli K-12，但对OI 57：H7的ATP含量无影响。乙酸对E. coliO 157：H7，乙酸盐处理的K-12细胞比未处理的对照细胞具有更多的钾。根据这些结果，乙酸和CCCP对E.杆菌比较了E. coliO 157：H7和K-12的细胞内pH值、乙酸积累量和细胞内钾含量之间存在相关性。大肠杆菌K-12比O 157：H7保持更高的细胞内pH，积累更多的乙酸盐，并具有更高的细胞内钾。
Non-growing cells of Escherichia coli O157:H7 and K-12 that were incubated anaerobically in sodium phosphate buffer at pH 6.5 consumed glucose at a rate of approximately 8 mu mol.(mg protein)(-1).h(-1) and had intracellular pK values of 7.3 and 7.5, respectively. The uncoupler, carbonylcyanide-m-chlorophenylhydrazone (CCCP), caused a marked decrease in intracellular pH, ATP and potassium of both strains. Low concentrations of CCCP stimulated glucose consumption rate, but higher concentrations were inhibitory. Acetate also caused a decrease in intracellular pH, but it never caused a large decrease in glucose consumption rate. Acetate decreased the intracellular ATP of E. coli K-12, but it had no effect on the ATP of OI57:H7. Acetate had no effect on the intracellular potassium of E. coli O157:H7, and acetate-treated K-12 cells had even more potassium than untreated controls. Based on these results, acetate and CCCP appear to have different effects on E. coli. The comparison of E. coli O157:H7 and K-12 indicated that intracellular pH, acetate accumulation and intracellular potassium were related. E, coli K-12 maintained a higher intracellular pH than O157:H7, accumulated more acetate and had a greater intracellular potassium.