多位点序列分型方法在嗜麦芽窄食单胞菌分子分型中的应用

目的建立多位点序列分型方法（Multilocus sequence typing，MLST）分析嗜麦芽窄食单胞菌。方法提取嗜麦芽窄食单胞菌基因组DNA，选择文献报道的7个嗜麦芽窄食单胞菌管家基因进行PCR扩增，将目的基因PCR产物测序，测序结果与标准序列比对后上传至数据库（http：／／pubmlst．org／smaltophilia／），获得相应的7对管家基因组成的等位基因谱和序列分型编码（sequencetypes，STs），应用MLST方法分析68株嗜麦芽窄食单胞菌ST型的流行病学意义。结果对68株嗜麦芽窄食单胞菌菌株通过多位点序列分型方法分析，所有菌株均为同一新的ST型（sT87），该结果与现场流行病学的关系一致。结论MLST是一种方便、快速的分子生物学方法，实验室菌株资料可以比较，适用于嗜麦芽窄食单胞菌的进化关系、群体结构和长期的全球分子流行病学研究。

Multilocus sequence typing analysis of Stenotrophomonas maltophilia molecular typing

.Multilocus sequence typing （MLST） method was established for Stenotrophomonas maltophilia study. The genomic DNAs of S. maltophilia were extracted with genomic extraction kit. Seven house-keeping genes were selected as tar- get genes and PCR was applied. Sequencing, analysis and comparison of the 7 housekeeping genes were conducted. The alleles of seven housekeeping genes and sequence type （ST） codes were obtained from the web （http：//pubmlst. org/smaltophilia/）. A total of 68 S. maltophilia strains isolated from the same place were tested by MLST and the epidemiological significance on STs was analyzed. One novel ST （ST87） was found from all 68 S. maltophilia strains. The result of MLST was consistent with the field epidemiology. It＇s suggested that MLST is a convenient and rapid molecular method for S. maltophilia, and it is applicable to the study of evolutionary history, population structure and long-term global epidemiology of S. maltophilia.