Characterization of IS1541-like elements in Yersinia enterocolitica and Yersinia pseudotuberculosis

We characterized Yersinia enterocolitica and Yersinia pseudotuberculosis in sertion sequences related to insertion sequence 1541, recently identified i n Yersinia pestis. For each of the two species, two insertion sequence copi es were cloned and sequenced. Genetic elements from Y. pseudotuberculosis w ere almost identical to insertion sequence 1541, whereas these from Y. ente rocolitica were less related. Phylogenetic analysis of the putative transpo sases encoded by insertion sequences from the three pathogenic members of t he genus Yersinia showed that they clustered with those encoded by Escheric hia coli and Salmonella enterica elements belonging to the insertion sequen ce 200/insertion sequence 605 group. Insertion sequences originating from Y . pestis and Y. pseudotuberculosis constitute a monophyletic lineage distin ct from that of Y. enterocolitica. (C) 1999 Federation of European Microbio logical Societies. Published by Elsevier Science B.V. All rights reserved.