与真核细胞蛋白质外运方式不同 ,大肠杆菌分泌蛋白的合成和跨内膜转运是不偶联的 ,对于一些小分子蛋白质 (例如噬菌体M 13外壳蛋白 )不需要其它分子协助能自发保持松散构象从核糖体定位到质膜 ,而对于大的蛋白质分子 ,尤其含有疏水结构域或疏水信号肽 ,需要其它分子伴侣的协助以保持转运感受状态才能被有效转运。除了这种依赖Scc(secretory)蛋白的一般分泌途径以外 ,还存在其它Sec非依赖性的Tat途径〔1,2〕等。本文对大肠杆菌Sec依赖性蛋白质转运途径进行综述。 Unlike eukaryotic protein exocytosis, E. coli secreted protein synthesis and transmembrane trafficking are uncoupled and do not require additional molecules for some small molecule proteins (eg, phage M 13 coat protein) to spontaneously maintain a loose conformation From ribosomes to the plasma membrane, and for large protein molecules, especially containing hydrophobic domains or hydrophobic signal peptides, require the assistance of other chaperones in order to maintain their transit status for efficient transport. In addition to this general secretory pathway that relies on the secretory proteins of Scc, there are other Sec-independent Tat pathways [1,2] and others. This article reviews the E. coli Sec-dependent protein transport pathways.