Detection of diverse new Francisella-like bacteria in environmental samples
Detection of diverse new Francisella-like bacteria in environmental samples
复制标题
DOI：
10.1128/aem.71.9.5494-5500.2005
复制
发表时间：
2005-09-01
影响因子：
4.4
通讯作者：
Kuske, CR
中科院分区：
文献类型：
--
作者：
Barns, SM;Grow, CC;Kuske, CR
在德克萨斯州休斯顿的气溶胶样品中检测到推定的Francisella物种后，我们调查了该地区的土拉菌，Francisella tularensis和相关物种的土壤和水样。最初的调查使用16S rRNA基因引物，通过PCR扩增环境样品中的DNA提取物来检测弗朗西斯菌属物种和相关生物。该分析表明，与弗朗西斯菌相关的序列存在于一个水和七个土壤样品中。这是第一次报告的检测弗朗西斯菌相关物种的土壤样品中的DNA为基础的方法。PCR产物的克隆和测序表明存在多种弗朗西斯相关物种。两个土壤样品的序列与先前报道的F.土拉菌分离物，可能代表新的亚种。利用开发的用于检测和区分F. tularensis亚种支持了与已知F.土拉菌菌株。虽然这些微生物的致病性尚不清楚，但它们有可能在F。土拉菌特异性测定。类似地，鉴定了一个潜在的新亚种Francisella philomiragia。获得的大多数序列，而更相似的弗朗西斯比任何其他属，是从已知的物种，并形成了几个新的分支可能代表新的物种或属。这项研究的结果修订了我们对弗朗西斯菌多样性和分布的理解，并对土拉菌流行病学和我们检测生物恐怖活动的能力产生了影响。
Following detection of putative Francisella species in aerosol samples from Houston, Texas, we surveyed soil and water samples from the area for the agent of tularemia, Francisella tularensis, and related species. The initial survey used 16S rRNA gene primers to detect Francisella species and related organisms by PCR amplification of DNA extracts from environmental samples. This analysis indicated that sequences related to Francisella were present in one water and seven soil samples. This is the first report of the detection of Francisella-related species in soil samples by DNA-based methods. Cloning and sequencing of PCR products indicated the presence of a wide variety of Francisella-related species. Sequences from two soil samples were 99.9% similar to previously reported sequences from F. tularensis isolates and may represent new subspecies. Additional analyses with primer sets developed for detection and differentiation of F. tularensis subspecies support the finding of very close relatives to known F. tularensis strains in some samples. While the pathogenicity of these organisms is unknown, they have the potential to be detected in F. tularensis-specific assays. Similarly, a potential new subspecies of Francisella philomiragia was identified. The majority of sequences obtained, while more similar to those of Francisella than to any other genus, were phylogenetically distinct from known species and formed several new clades potentially representing new species or genera. The results of this study revise our understanding of the diversity and distribution of Francisella and have implications for tularemia epidemiology and our ability to detect bioterrorist activities.