Hayashi S, Wu H C
J Bacteriol. 1985 Mar;161(3):949-54. doi: 10.1128/jb.161.3.949-954.1985.
The export of lipoprotein has been found to be affected in both secA and secY mutants of Escherichia coli which are defective in the secretion of a number of outer membrane and periplasmic proteins. The kinetics of accumulation of prolipoprotein upon a temperature shift to 42 degrees C is indistinguishable from that of pre-OmpA protein accumulation in the secA mutant. In both secA and secY mutants, the accumulated prolipoprotein is unmodified with glyceride and localized in the cytoplasmic membrane. We conclude from these results that the early steps in protein export are common to prolipoprotein and non-lipoprotein precursors. The pathways for the export of these two groups of precursor proteins diverge with regard to the modification and processing reactions which are late events in the export process.
已发现脂蛋白的输出在大肠杆菌的secA和secY突变体中均受到影响，这些突变体在多种外膜蛋白和周质蛋白的分泌方面存在缺陷。温度转移至42℃时前脂蛋白的积累动力学与secA突变体中前OmpA蛋白积累的动力学无法区分。在secA和secY突变体中，积累的前脂蛋白均未被甘油酯修饰，并定位于细胞质膜中。从这些结果我们得出结论，蛋白质输出的早期步骤对于前脂蛋白和非脂蛋白前体是共同的。这两组前体蛋白的输出途径在修饰和加工反应方面有所不同，而修饰和加工反应是输出过程中的后期事件。
