Ribosomal protein L2 associates with E. coli HtpG and activates its ATPase activity
Ribosomal protein L2 associates with E. coli HtpG and activates its ATPase activity
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DOI：
10.1016/j.bbrc.2010.08.047
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发表时间：
2010-09-17
影响因子：
3.1
通讯作者：
Motojima, Fumihiro
中科院分区：
文献类型：
--
作者：
Motojima-Miyazaki, Yuko;Yoshida, Masasuke;Motojima, Fumihiro
虽然真核生物Hsp90已经得到了广泛的研究，但其细菌同源物HtpG的功能仍然不清楚。本文报道了在45℃最低温度下培养的大肠杆菌中，50S核糖体蛋白L2被发现是His标记的HtpG的结合蛋白，但其他变性蛋白不能激活HtpG的ATPase活性。用HtpG和L2的结构域衍生物分析表明，L2的C-末端结构域和HtpG的中间到C-末端结构域对相互作用是重要的。在生理盐浓度下，12处于变性状态，可被HtpG以及其他伴侣蛋白DNAK/DNAJ/GRPE和GroEL/GroES识别。随着L2浓度的增加，HtpG的ATPase显示，L2分子与二聚体HtpG结合，在100 mM KCl时的表观K-D为0.3mM，在200 mMKCl时为3.3mM。(C)2010 Elsevier Inc.保留所有权利。
Although eukaryotic Hsp90 has been studied extensively, the function of its bacterial homologue HtpG remains elusive. Here we report that 50S ribosomal protein L2 was found as an associated protein with His-tagged HtpG from Escherichia coli cultured in minimum medium at 45 C. L2 specifically activated ATPase activity of HtpG, but other denatured proteins did not. The analysis using domain derivatives of HtpG and L2 showed that C-terminal domain of L2 and the middle to C-terminal domain of HtpG are important for interaction. At physiological salt concentration, 12 was denatured state and was recognized by HtpG as well as other chaperones, DnaK/DnaJ/GrpE and GroEL/GroES. The ATPase of HtpG at increasing concentration of L2 indicated that an L2 molecule bound to a dimer HtpG with apparent K-D of 0.3 mu M at 100 mM KCl and 3.3 mu M at 200 mM KCl. (C) 2010 Elsevier Inc. All rights reserved.