Tiba Monique Ribeiro, Yano Tomomasa, Leite Domingos da Silva
Departamento de Microbiologia e Imunologia, Laboratório de antígenos Bacterianos II, Instituto de Biologia, Universidade Estadual de Campinas, Cidade Universitária Zeferino Vaz, Campinas, SP, Brasil.
Rev Inst Med Trop Sao Paulo. 2008 Sep-Oct;50(5):255-60. doi: 10.1590/s0036-46652008000500001.
Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (alpha-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.
粘附素（P菌毛、S菌毛、1型菌毛和无纤毛粘附素）、毒素（α-溶血素和1型细胞毒性坏死因子）、铁摄取系统（气杆菌素）以及宿主防御规避机制（荚膜或脂多糖）已被证明在与尿路感染相关的大肠杆菌菌株中普遍存在。在本研究中，采用聚合酶链反应（PCR）分析法对162株来自膀胱炎患者的尿路致病性大肠杆菌（UPEC）菌株进行了基因分型。我们针对毒力相关基因papC、papE/F、papG等位基因、fimH、sfa/foc、afaE、hly、cnf-1、usp、cdtB、iucD和kpsMTII开发了三种多重PCR检测方法，这些基因先前已在UPEC菌株中被鉴定出来。PCR检测结果显示，有158株fimH（97.5%）、86株kpsMTII（53.1%）、53株papC/papEF/papG（32.7%）、45株sfa（27.8%）、42株iucD（25.9%）、41株hly（25.3%）、36株usp（22.2%）、30株cnf-1（18.5%）和10株afa（6.2%）菌株。没有菌株cdtB呈阳性。在本研究中，我们还证明了单个菌株内可能存在多种粘附素，并且几种毒力基因可能会联合出现。
