Hancock Viktoria, Seshasayee Aswin S, Ussery David W, Luscombe Nicholas M, Klemm Per
Microbial Adhesion Group, Risø DTU, Technical University of Denmark, Building 301, 2800 Kgs Lyngby, Denmark.
Mol Genet Genomics. 2008 May;279(5):523-34. doi: 10.1007/s00438-008-0330-9.
Escherichia coli strains are the major cause of urinary tract infections in humans. Such strains can be divided into virulent, UPEC strains causing symptomatic infections, and asymptomatic, commensal-like strains causing asymptomatic bacteriuria, ABU. The best-characterized ABU strain is strain 83972. Global gene expression profiling of strain 83972 has been carried out under seven different sets of environmental conditions ranging from laboratory minimal medium to human bladders. The data reveal highly specific gene expression responses to different conditions. A number of potential fitness factors for the human urinary tract could be identified. Also, presence/ absence data of the gene expression was used as an adaptive genomics tool to model the gene pool of 83972 using primarily UPEC strain CFT073 as a scaffold. In our analysis, 96% of the transcripts filtered present in strain 83972 can be found in CFT073, and genes on six of the seven pathogenicity islands were expressed in 83972. Despite the very different patient symptom profiles, the two strains seem to be very similar. Genes expressed in CFT073 but not in 83972 were identified and can be considered as virulence factor candidates. Strain 83972 is a deconstructed pathogen rather than a commensal strain that has acquired fitness properties.
大肠杆菌菌株是人类尿路感染的主要原因。这类菌株可分为导致有症状感染的致病性尿道致病性大肠杆菌（UPEC）菌株和导致无症状菌尿（ABU）的无症状、类似共生菌的菌株。最具代表性的ABU菌株是83972菌株。已在从实验室基本培养基到人类膀胱等七种不同环境条件下对83972菌株进行了全基因组表达谱分析。数据揭示了对不同条件的高度特异性基因表达反应。可以确定一些人类尿道潜在的适应性因素。此外，基因表达的存在/缺失数据被用作一种适应性基因组学工具，主要以UPEC菌株CFT073为支架来模拟83972菌株的基因库。在我们的分析中，83972菌株中筛选出的转录本有96%可在CFT073中找到，并且七个致病岛中有六个上的基因在83972中表达。尽管患者症状表现差异很大，但这两种菌株似乎非常相似。已鉴定出在CFT073中表达但在83972中不表达的基因，这些基因可被视为毒力因子候选基因。83972菌株是一种解构的病原体，而不是获得了适应性特性的共生菌株。
