DNA同源性分析最终确定新疆中华根瘤菌(Sinorhizobium xinjiangensis)为一独立种  

SINORHIZOBIUM XINJIANGENSIS AS AN INDEPENDENT SPECIES CONFIRMED BY DNA HOMOLOGY ANALYSIS

作　　者：彭桂香[1] 谭志远[1] 陈文新[1] 

机构地区：[1]中国农业大学生物学院,北京100094

出　　处：《应用与环境生物学报》2000年第6期572-576,共5页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金!(No :39730 0 10 )重点资助项目

摘　　要：针对S .xinjiangensis分类地位的争议 ,从新疆再次分离获得 34株快生大豆根瘤菌 ,在 16SrDNAPCR-RFLP分析和SDS全细胞蛋白电泳分群的基础上 ,进行了 16SrDNA全序列相似性和DNA同源性分析 .所测 4个菌株和S .fredii模式菌株USDA 2 0 5的 16SrDNA全序列有很高的相似性 .而DNA同源性分析说明新分离的菌株代表与原定的S .xinjiangensis为一个DNA同源群 .其模式菌株CCBAU 110与S .fredii的 2株参比菌株USDA194、2 0 48之间的DNA同源性分别为 31.5 %和 2 8.7% .S .fredii的模式菌株USDA 2 0 5与新分离的菌株代表及原定的S .xinjiangensis的模式菌株和 2个参比菌株之间的DNA同源性为 2 0 .8%～ 39% ,远低于 70 % .属于种水平上的差异 .按照国际细菌分类委员会以DNA同源性≥ 70 %且△Tm≤ 5℃作为定种的标准 ,S .xinjiangensis是Sinorhizobium属中不同于S .fredii的一个独立的种 .表 3参 2In this study, based on the results from 16S rDNA PCR RFLP of 34 fast growing soybean rhizobia strains isolated from Xinjiang in comparison with several type and reference strains of related species, and SDS PAGE whole cell protein patterns of new representative isolates and other strains in Sinorhizobium , new representative isolates were further analyzed by 16S rDNA full sequencing, G+C mol% tests and DNA DNA hybridization. 4 strains were analyzed by 16S rDNA full sequencing, indicating that type strain CCBAU 110 of S. xinjiangensis and type strain USDA 205 of S. fredii shared high similarity. The DNA homologies indicated that new representative isolates and S. xinjiangensis were of the same DNA homology groups. The DNA homologies between CCBAU 110 and the reference strains of S. fredii : USDA 194, 2048 were 31.5% and 28.7%, respectively. The DNA DNA hybridization values between USDA 205 and CCBAU 110, 2 reference strains of S. xinjiangensis , representative of new isolates were 20.8%～39%, which confirmed that S. xinjiangensis and S. fredii belonged to the different DNA homology groups, and S. xinjiangensis was an unique, independent species in Sinorhizobium . Tab 3, Ref 20

关 键 词：新疆中华根瘤菌 快生大豆根瘤菌 DNA同源性分析 

分 类 号：Q939.114.09[生物学—微生物学]