ATP IS ESSENTIAL FOR PROTEIN TRANSLOCATION INTO ESCHERICHIA-COLI MEMBRANE-VESICLES
ATP IS ESSENTIAL FOR PROTEIN TRANSLOCATION INTO ESCHERICHIA-COLI MEMBRANE-VESICLES
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DOI：
10.1073/pnas.82.13.4384
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发表时间：
1985-01-01
影响因子：
11.1
通讯作者：
TAI, PC
中科院分区：
文献类型：
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作者：
CHEN, LL;TAI, PC
研究了碱性磷酸酶和外膜蛋白OmpA在允许翻译后转位和预先去除蛋白质合成所需各种组分的条件下转位到大肠杆菌膜小泡中所需的能量。转位可以由ATP生成系统支持，或者，不太好的是，由D-乳酸氧化产生的质子动力支持；后者可能通过从残留的结合核苷酸生成ATP来起作用。当使用质子动力抑制剂或当ATP被大肠杆菌甘油激酶进一步耗尽时，D-乳酸不再支持易位。在存在质子解偶联剂或H+-ATPase F1部分膜有缺陷的情况下，ATP仍能支持蛋白质的转运。在这个翻译后系统中，蛋白质转位需要ATP(可能在共译转位中也是如此)；质子推动力可能起作用，但似乎不是必需的。
The energy requirement for translocation of alkaline phosphatase and the outer membrane protein OmpA into E. coli membrane vesicles was studied under conditions that permit posttranslational translocation and prior removal of various components necessary for protein synthesis. Translocation could be supported by an ATP-generating system or, less well, by the protonmotive force generated by D-lactate oxidation; the latter might act by generating ATP from residual bound nucleotides. When protonmotive force inhibitors were used or when ATP was further depleted by E. coli glycerol kinase, D-lactate no longer supported the translocation. ATP could still support protein translocation in the presence of proton uncouplers or with membranes defective in the F1 fraction of the H+-ATPase. ATP is required for protein translocation in this posttranslation system (and probably also in cotranslation translocation); the protonmotive force may contribute but does not appear to be essential.