Multilocus Sequence Typing of Bordetella pertussis Based on Surface Protein Genes

Abstract

Despite more than 50 years of vaccination, Bordetella pertussis has remained endemic in The Netherlands, causing epidemic outbreaks every 3 to 5 years. Strain variation may play a role in the persistence of B. pertussis and was studied by sequencing 15 genes coding for surface proteins, including genes for all five components of acellular pertussis vaccines: pertussis toxin (Ptx), pertactin (Prn), filamentous hemagglutinin, and fimbriae (Fim2 and Fim3). A low level of allelic variation was observed, confirming a recent evolutionary origin of B. pertussis. In modern isolates, polymorphism was observed only in prn, ptxS1, ptxS3, and tcfA. Polymorphism in ptxS1, ptxS3, and tcfA was used to categorize isolates in multilocus sequence types (MLSTs). Analysis of Dutch isolates from 1949 to 1999 revealed five MLSTs, which showed a highly dynamic temporal behavior. We observed significant changes in the MLSTs after the introduction of pertussis vaccination in The Netherlands. Epidemic years were found to be associated with the expansion of MLST-4 or MLST-5. MLST-5 showed a remarkable expansion from 10% in 1997 to 80% in 1999. The MLST analysis was extended to a number of widely separated geographic regions: Finland, Italy, Japan, and the United States. MLST-4 and MLST-5 were found to dominate in Italy and the United States. In Finland and Japan, MLST-3 and MLST-2, respectively, were predominant. Thus, although each region showed distinctive MLST frequencies, in three of the five regions MLST-4 and MLST-5 were predominant. These types may represent newly emerged, successful clones. The identification of highly successful clones may shed light on the question of how B. pertussis is able to maintain itself in vaccinated populations.

Lactobacillus suntoryeus sp. nov., isolated from malt whisky distilleries

“…54 %) with those of the Japanese strains. Surface-protein genes are subject to greater selective pressure and change more rapidly than housekeeping genes such as tuf, particularly in pathogenic bacteria exposed to immune responses (van Loo et al, 2002). The inconsistencies between the slp tree and those derived from 16S rRNA and tuf genes indicated that the slp gene may not provide an accurate picture of the phylogenetic relationships of these organisms and may be subject to lateral transfer.…”

Use of molecular diversity of Mycoplasma gallisepticum by gene-targeted sequencing (GTS) and random amplified polymorphic DNA (RAPD) analysis for epidemiological studies

“…The identification of gene polymorphism in bacteria by nucleotide sequence analysis of genes encoding antigenic surface proteins jointly with genes encoding housekeeping proteins has been proven useful in the surveillance of pathogenic bacteria (Byun et al, 1999;Maiden et al, 1998;van Loo et al, 2002;Kotetishvili et al, 2003). Particularly multilocus sequence typing (MLST) schemes where data can be stored, analysed and queried through a central web server have permitted local and global epidemiology studies of several infectious agents (Chan et al, 2001).…”

Toward a Wolbachia Multilocus Sequence Typing System: Discrimination of Wolbachia Strains Present in Drosophila Species

“…This method was first described by Maiden and colleagues [34] as a tool for strain discrimination of Neisseria meningitis strains and has since been used extensively to distinguish strains of pathogenic bacteria [18,52,62]. MLST is based on direct nucleotide sequencing of a target locus, to which a unique and arbitrary allele number is assigned.…”