Comparative proteomic analysis of Vibrio cholerae O139, O22, O155 and El Tor biotype epidemic strains

The purposes of this study are to compare the proteome of Vibrio cholerae O139 strains with that of O22, O155 and El Tor biotype epidemic strains, and to identify whether O139 strains have a close relation with the latter. Proteins of two V.cholerae serogroup O139 strains, two El Tor biotype epidemic strains, one O22 strain, and one O155 strain were separated by two-dimensional gel electrophoresis (2-DE); the silver stained 2-DE gels were scanned with digital ImageScanner and analyzed with ImageMaster 2D Elite 3.10 software. Similarities of protein maps between these strains were analyzed. The two O139 strains had 86% proteins in common; the two El Tor biotype epidemic strains showed 84% proteins in common; O139 strains shared 67%, 47% and 45% proteins with El Tor biotype epidemic strains, O22 and O155 strains respectively. Although the proteome of O139 strains have close similarity to that of El Tor biotype epidemic strains, great disparities exist. O139 strains may not originate from El Tor biotype directly, and a transition strain may exist.