O'Callaghan R J, Bundy L, Bradley R, Paranchych W
J Bacteriol. 1973 Jul;115(1):76-81. doi: 10.1128/jb.115.1.76-81.1973.
The arsenate poisoning of R17 phage eclipse in Escherichia coli cultures grown in glycerol-containing medium has been found to be mediated by a dramatic loss in cell-associated F pili. Poisoning was very rapid and was nearly complete within 3 min at 37 C. The loss of pili was reflected by a 90% reduction in the ability of these cells to attach ribonucleic acid phage and by a reduction in the pili-per-cell ratio from 1.36 to 0.04 as determined by electron microscopy. Neither the integrity of the pilus per se nor the attachment process was affected by arsenate, for cell-free pili treated with arsenate retained the ability to attach phage. The arsenate effect on F piliation could be reversed readily without any loss in cell viability. This restoration of pili occurred under conditions of inhibited protein synthesis, implying that pools of pili protein exist in cells. In contrast to this phenomenon, cells grown in glucose-containing media were mainly resistant to arsenate poisoning as determined by phage attachment and the number of pili per cell. These results implied that arsenate poisons the ability of cells to synthesize and maintain F pili under certain specific conditions. The possible mechanism of this poisoning is discussed.
已发现，在含甘油培养基中生长的大肠杆菌培养物中，R17噬菌体潜伏期的砷酸盐中毒是由细胞相关F菌毛的显著丧失介导的。中毒非常迅速，在37℃下3分钟内几乎完全发生。菌毛的丧失表现为这些细胞附着核糖核酸噬菌体的能力降低90%，并且通过电子显微镜测定，每个细胞的菌毛比率从1.36降至0.04。菌毛本身的完整性和附着过程均不受砷酸盐影响，因为用砷酸盐处理的无细胞菌毛保留了附着噬菌体的能力。砷酸盐对F菌毛形成的影响可以很容易地逆转，而细胞活力没有任何损失。菌毛的这种恢复发生在蛋白质合成受抑制的条件下，这意味着细胞中存在菌毛蛋白库。与此现象形成对比的是，通过噬菌体附着和每个细胞的菌毛数量测定，在含葡萄糖培养基中生长的细胞对砷酸盐中毒主要具有抗性。这些结果表明，在某些特定条件下，砷酸盐会毒害细胞合成和维持F菌毛的能力。本文讨论了这种中毒的可能机制。
