Ogino Hidetaka, Wachi Masaaki, Ishii Akihiro, Iwai Noritaka, Nishida Tetsuya, Yamada Sakuo, Nagai Kazuo, Sugai Motoyuki
Department of Bioengineering, Tokyo Institute of Technology, 4259-B-38 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan.
Genes Cells. 2004 Sep;9(9):765-71. doi: 10.1111/j.1365-2443.2004.00770.x.
When Escherichia coli is treated with penicillin, the envelopes bulge at the centre of the cells and the cells then lyse. The bulges expand into vesicle-like structures termed penicillin-induced vesicles. We have developed a method to isolate these structures and have shown that they contain mainly membrane proteins plus a high concentration of a 60 kDa protein. The N-terminal amino acid sequence of the protein is identical to that of GroEL protein. Western blotting analysis using anti-GroEL antibody showed that GroEL is indeed concentrated in the vesicles. Indirect immuno-fluorescence microscopy showed that GroEL protein is localized at the centre of the cells at the site of formation of FtsZ-rings. Localization of GroEL is dependent on FtsZ but not other Fts proteins. GroEL mutants formed elongated cells having no or asymmetrically localized FtsZ-rings at the restrictive temperature. These findings suggest a possible role of the GroEL protein in cell division.
当用青霉素处理大肠杆菌时，细胞包膜会在细胞中央鼓起，随后细胞裂解。这些凸起会扩展成囊泡样结构，称为青霉素诱导囊泡。我们开发了一种分离这些结构的方法，并表明它们主要包含膜蛋白以及高浓度的一种60 kDa蛋白。该蛋白的N端氨基酸序列与GroEL蛋白的相同。使用抗GroEL抗体的蛋白质印迹分析表明，GroEL确实集中在囊泡中。间接免疫荧光显微镜显示，GroEL蛋白定位在细胞中央FtsZ环形成的部位。GroEL的定位依赖于FtsZ，而不依赖于其他Fts蛋白。在限制温度下，GroEL突变体形成了没有FtsZ环或FtsZ环不对称定位的细长细胞。这些发现提示了GroEL蛋白在细胞分裂中可能发挥的作用。
