[Molecular genetic features of structure of gene coding tracheal colonization factor in Bordetella pertussis strains].

Aim: Comparative analysis of structure of tcfA gene coding tracheal colonization factor of Bordetella pertussis strans isolated in Moscow from patients with pertussis.

Materials And Methods: Ninety-seven strains of B. pertussis isolated in different periods of pertussis infection epidemic process (1948 - 1989--from collection of Gabrichevsky Moscow Research Institute of Epidemiology and Microbiology; 1990 - 2007--isolated in Moscow from patients with pertussis) were studied. Primers for amplification of tcfA gene region with size 945 n.p. were used. Amplicons obtained in PCR were used for sequencing. Nucleotide sequences of tcfA gene types of B. pertussis strains were matched to EMBL/GenBank database.

Results: Sequencing of tcfA gene fragments revealed two sequence variants. Ninety-six of 97 studied B. pertussis strains had the same sequence variant--variant 1. The one strain was characterized by other nucleotide sequence--variant 2, which differed from variant 1 by presence of insertion g in position 396 that led to reading frame shift.

Conclusion: The structure of tcfA gene circulating population of B. pertussis strains is homogenous and is characterized by presence of "vaccine" allele dominating in majority of countries in the world.