REARRANGEMENTS IN THE GENOMES OF VIBRIO-CHOLERAE STRAINS BELONGING TODIFFERENT SEROVARS AND BIOVARS

The intron-encoded enzyme I-CeuI provides an excellent tool for rapidl y examining the organization of genomes of related species of bacteria . Vibro cholerae strains belonging to serovars O1 and O139 have 9 I-Ce uI sites in their genomes, and V. cholerae strains belonging to serova rs non-O1 and non-O139 have 10 I-CeuI sites in their genomes, This inf ormation can be used as a criterion to differentiate O1 strains from n on-O1 and non-O139 strains, To our knowledge, intraspecies variation i n the number of rrn operons has not been reported in any other organis m, Our data revealed extensive restriction fragment length polymorphis m based on a comparison of the I-CeuI digestion profiles of strains be longing to different serovars and biovars, From the analysis of partia l digestion products, I-CeuI macrorestriction maps of several classica l, El Tor, and O139 strains were constructed. While the linkage maps a re conserved within biovars, linkage maps vary substantially between b iovars.