Himeno Hyouta, Hanawa-Suetsugu Kyoko, Kimura Takatsugu, Takagi Kuniaki, Sugiyama Wakana, Shirata Shinobu, Mikami Tomoyuki, Odagiri Fujiko, Osanai Yukiko, Watanabe Daisuke, Goto Simon, Kalachnyuk Liliya, Ushida Chisato, Muto Akira
Department of Biochemistry and Biotechnology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki 036-8561, Japan.
Nucleic Acids Res. 2004 Oct 5;32(17):5303-9. doi: 10.1093/nar/gkh861. Print 2004.
The GTPase activity of Escherichia coli YjeQ, here named RsgA (ribosome small subunit-dependent GTPase A), has been shown to be significantly enhanced by ribosome or its small subunit. The enhancement of GTPase activity was inhibited by several aminoglycosides bound at the A site of the small subunit, but not by a P site-specific antibiotic. RsgA stably bound the small subunit in the presence of GDPNP, but not in the presence of GTP or GDP, to dissociate ribosome into subunits. Disruption of the gene for RsgA from the genome affected the growth of the cells, which predominantly contained the dissociated subunits having only a weak activation activity of RsgA. We also found that 17S RNA, a putative precursor of 16S rRNA, was contained in the small subunit of the ribosome from the RsgA-deletion strain. RsgA is a novel GTPase that might provide a new insight into the function of ribosome.
大肠杆菌YjeQ（此处命名为RsgA，即核糖体小亚基依赖性GTP酶A）的GTP酶活性已被证明会受到核糖体或其小亚基的显著增强。几种结合在小亚基A位点的氨基糖苷类药物会抑制GTP酶活性的增强，但P位点特异性抗生素则不会。在存在GDPNP的情况下，RsgA会稳定地结合小亚基，但在存在GTP或GDP时则不会，从而使核糖体解离成亚基。从基因组中破坏RsgA基因会影响细胞的生长，这些细胞主要包含仅具有弱RsgA激活活性的解离亚基。我们还发现，17S RNA（一种推测的16S rRNA前体）存在于来自RsgA缺失菌株的核糖体小亚基中。RsgA是一种新型GTP酶，可能会为核糖体的功能提供新的见解。
