[Structural organization of a segment of chromosome, containing the vir gene of Bordetella pertussis].

To study the structural arrangement of the chromosomal region containing vir genes of Bordetella pertussis the corresponding 15 kb fragment of Bordetella pertussis chromosomal DNA has been cloned. The sequence homology to an earlier characterized Bordetella pertussis genetical element RSBP1 and flanked by two 400 bp inverted repeats has been shown to be located at an end of a BamHI fragment. The restriction map of Bordetella pertussis 475 coincides with the previously published maps of Bordetella pertussis Tohama and 18323 permitting one to conclude the definite conservatism of the cloned sequence. The preliminary data obtained make possible mapping of the RSBP1 homologous sequence adjacent to adenylate cyclase, agglutinin 2 and pertussis toxin genes. The possible role of RSBP1 elements in the regulation of Bordetella virulence is suggested.