Lee Chang Kyu, Gi Hyun Mi, Cho Yunjung, Kim Young Kee, Lee Kap No, Song Ki-Joon, Song Jin-Won, Park Kwang Sook, Park Eun Mi, Lee Hyeyoung, Bai Gill-Han
Department of Clinical Pathology, College of Medicine, Korea University, Seoul, Korea.
Microbiol Immunol. 2004;48(2):83-90. doi: 10.1111/j.1348-0421.2004.tb03492.x.
The species identification within Mycobacterium terrae complex has been known to be very difficult. In this study, the genomic diversity of M. terrae complex with eighteen clinical isolates, which were initially identified as M. terrae complex by phenotypic method, was investigated, including that of three type strains (M. terrae, M. nonchromogenicum, and M. triviale ). 16S rRNA and 65-kDa heat shock protein (hsp 65) gene sequences of mycobacteria were determined and aligned with eleven other references for the comparison using similarity search against the GenBank and Ribosomal Database Project II (RDP) databases. 16S rRNA and hsp 65 genes of M. terrae complex showed genomic heterogeneity. Amongst the eighteen clinical isolates, nine were identified as M. nonchromogenicum, eight as M. terrae, one as M. mucogenicum with the molecular characteristic of rapid growth. M. nonchromogenicum could be subdivided into three subgroups, while M. terrae could be subdivided into two subgroups using a 5 bp criterion (>1% difference). Seven isolates in two subgroups of M. nonchromogenicum were Mycobacterium sp. strain MCRO 6, which was closely related to M. nonchromogenicum. The hsp 65 gene could not differentiate one M. nonchromogenicum from M. avium or one M. terrae from M. intracellulare. The nucleotide sequence analysis of 16S rRNA and hsp 65 genes was shown to be useful in identifying the M. terrae complex, but hsp 65 was less discriminating than 16S rRNA.
已知在土地分枝杆菌复合群内进行菌种鉴定非常困难。在本研究中，对18株临床分离株（最初通过表型方法鉴定为土地分枝杆菌复合群）的基因组多样性进行了研究，其中包括三株模式菌株（土地分枝杆菌、非产色分枝杆菌和琐事分枝杆菌）。测定了分枝杆菌的16S rRNA和65-kDa热休克蛋白（hsp 65）基因序列，并与其他11个参考文献进行比对，以通过针对GenBank和核糖体数据库项目II（RDP）数据库的相似性搜索进行比较。土地分枝杆菌复合群的16S rRNA和hsp 65基因显示出基因组异质性。在这18株临床分离株中，9株被鉴定为非产色分枝杆菌，8株为土地分枝杆菌，1株为具有快速生长分子特征的产黏液分枝杆菌。非产色分枝杆菌可细分为三个亚组，而土地分枝杆菌可使用5 bp标准（>1%差异）细分为两个亚组。非产色分枝杆菌两个亚组中的7株分离株为分枝杆菌属菌株MCRO 6，它与非产色分枝杆菌密切相关。hsp 65基因无法区分非产色分枝杆菌与鸟分枝杆菌，或土地分枝杆菌与胞内分枝杆菌。16S rRNA和hsp 65基因的核苷酸序列分析在鉴定土地分枝杆菌复合群中显示出有用性，但hsp 65的鉴别能力不如16S rRNA。
