Zhao Jing-Yi, Xia Zhi-Jie, Sun Xia, Zhong Li, Jiang De-Ming, Liu Hong, Wang Jing, Qin Zhong-Jun, Li Yue-Zhong
State Key Laboratory of Microbial Technology, College of Life Science, Shandong University, Jinan 250100, People's Republic of China.
Biochem Biophys Res Commun. 2008 May 23;370(1):140-4. doi: 10.1016/j.bbrc.2008.03.045. Epub 2008 Mar 18.
A locus (kmr) responsible for aminoglycosides-resistance of Sorangium cellulosum was cloned and characterized in Myxococcus xanthus. The gene kmr encodes a putative rRNA methyltransferase. Expression of the complete ORF endowed the Myxococcus transformants with the resistance to aminoglycosidic antibiotics of kanamycin, apramycin, gentamycin, neomycin, and tobramycin at an extraordinary high-level (MIC, higher than 500 microg/ml). However, the gene did not function in Escherichia coli cells. In Sorangium genome, the gene kmr was followed by a putative integrase gene, and was highly homologous in different Sorangium strains. The Sorangium rRNA methyltransferase sequence was in low similarity to the reported 16S rRNA methyltransferases, and their resistance spectrums were also different. The results indicate that the rRNA methyltransferase (Kmr) in Sorangium strains is a new member of the rRNA methyltransferases family.
一个负责纤维素堆囊菌氨基糖苷类抗性的基因座（kmr）在黄色黏球菌中被克隆并进行了表征。基因kmr编码一种假定的rRNA甲基转移酶。完整开放阅读框的表达赋予黄色黏球菌转化体对卡那霉素、阿泊拉霉素、庆大霉素、新霉素和妥布霉素等氨基糖苷类抗生素的极高水平抗性（最低抑菌浓度，高于500微克/毫升）。然而，该基因在大肠杆菌细胞中不起作用。在堆囊菌基因组中，基因kmr后面跟着一个假定的整合酶基因，并且在不同的堆囊菌菌株中高度同源。堆囊菌的rRNA甲基转移酶序列与已报道的16S rRNA甲基转移酶相似度较低，它们的抗性谱也不同。结果表明，堆囊菌菌株中的rRNA甲基转移酶（Kmr）是rRNA甲基转移酶家族的一个新成员。
