Analysis of virulence factors in Uropathogenic Escherichia coli

Research Project

Project/Area Number	10670249
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Bacteriology (including Mycology)
Research Institution	Okayama University (1999) University of Tsukuba (1998)
Principal Investigator	KURAZONO Hisao Okayama University, Medical school, Professor, 医学部, 教授 (90186487)
Co-Investigator(Kenkyū-buntansha)	TERAI Akito Kyoto University, Medical school, Lecturer, 医学部, 講師 (50243019)
Project Period (FY)	1998 – 1999
Project Status	Completed (Fiscal Year 1999)
Budget Amount *help	¥3,200,000 (Direct Cost: ¥3,200,000) Fiscal Year 1999: ¥1,200,000 (Direct Cost: ¥1,200,000) Fiscal Year 1998: ¥2,000,000 (Direct Cost: ¥2,000,000)
Keywords	Uropathogenic / Escherichia coli / Virulence factors / Pathogenic islands / Pathogenic island / Zonula Occludens
Research Abstract	This study was initiated to search for a homologue of the Vibrio cholerae zot gene in uropathogenic Escherichia coli (UPEC) using a specific DNA probe. The faint signal obtained at low stringency with some UPEC strains associated with prostatitis cases prompted us to examine UPEC strains by PCR using primers designed from the conserved regions of the proteins of the Zot group of putative NTPases containing the classical NTP binding motif. This led to the discovery of a DNA fragment in UPEC strains which hybridized with a probe designed from the PCR. Further analysis of this DNA fragment revealed an ORF which was designated as uropathogenic specific protein (Usp). The gene encoding Usp was 1038 bp long and codes for 346 amino acids with an appropriate SD sequence. Upstream and downstream analysis of usp revealed motifs of prokaryotic consensus promoters and three small ORFs with SDs and ribosome binding sites transcribed in the same direction of usp. The proximity of these set of genes in a specific area of the bacterial chromosome resembling a block of genes preferentially associated with UPEC coupled with the presence of a motif matching that of a Tn3 transposon family lead us to believe that this could be an hitherto unknown pathogenicity island.