DebRoy Chitrita, Fratamico Pina M, Roberts Elisabeth, Davis Michael A, Liu Yanhong
Gastroenteric Disease Center, The Pennsylvania State University, Wiley Lab, Wiley Lane, University Park, PA 16802, USA.
Appl Environ Microbiol. 2005 Aug;71(8):4919-24. doi: 10.1128/AEM.71.8.4919-4924.2005.
The Escherichia coli O45 O-antigen gene cluster of strain O45:H2 96-3285 was sequenced, and conventional (singleplex), multiplex, and real-time PCR assays were designed to amplify regions in the wzx (O-antigen flippase) and wzy (O-antigen polymerase) genes. In addition, PCR assays targeting the E. coli O55 wzx and wzy genes were designed based on previously published sequences. PCR assays targeting E. coli O45 showed 100% specificity for this serogroup, whereas by PCR assays specific for E. coli O55, 97/102 strains serotyped as E. coli O55 were positive for wzx and 98/102 for wzy. Multiplex PCR assays targeting the E. coli O45 and the E. coli O55 wzx and wzy genes were used to detect the organisms in fecal samples spiked at levels of 10(6) and 10(8) CFU/0.2 g feces. Thus, the PCR assays can be used to detect and identify E. coli serogroups O45 and O55.
对O45:H2 96-3285菌株的大肠杆菌O45 O抗原基因簇进行了测序，并设计了常规（单重）、多重和实时PCR检测方法，以扩增wzx（O抗原翻转酶）和wzy（O抗原聚合酶）基因中的区域。此外，基于先前发表的序列设计了针对大肠杆菌O55 wzx和wzy基因的PCR检测方法。针对大肠杆菌O45的PCR检测方法对该血清型具有100%的特异性，而通过针对大肠杆菌O55的特异性PCR检测方法，102株被血清分型为大肠杆菌O55的菌株中，97株wzx呈阳性，98株wzy呈阳性。针对大肠杆菌O45以及大肠杆菌O55 wzx和wzy基因的多重PCR检测方法用于检测粪便样本中添加量为10(6)和10(8) CFU/0.2 g粪便的细菌。因此，PCR检测方法可用于检测和鉴定大肠杆菌O45和O55血清型。
