RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISM OF PCR AMPLIFIED PAPE GENE-PRODUCTS IS CORRELATED WITH COMPLETE SEROTYPE AMONG UROPATHOGENIC ESCHERICHIA-COLI ISOLATES

Using whole bacteria, rather than extracted, purified DNA samples, we amplified the papE gene sequences from 63 Escherichia coil isolates be longing to O serogroups O1, O2 and O6. These isolates were from collec tions separated temporally as well as geo graphically: from four citie s in the US and one in Sweden. PCR amplified papE products were digest ed with restriction endonucleases and the relative sizes of the fragme nts compared for each strain. For 41 of the strains, we found a correl ation between the papE restriction fragment length polymorphism (RFLP) and the complete serotype. Furthermore, we were able to detect the pr esence of duplicate copies of the gene in 14 of the isolates; these 14 isolates were among the 22 that did not exhibit a correlation between the RFLP of their amplified papE sequences and their complete serotyp e. We conclude that RFLP analysis of PCR products is a rapid and relat ively simple method for examining the DNA of E. coli containing the pa p gene sequence. (C) 1996 Academic Press Limited.