Comparative genomic assessment of Multi-Locus Sequence Typing: rapid accumulation of genomic heterogeneity among clonal isolates of Campylobacter jejuniReportar como inadecuado

Comparative genomic assessment of Multi-Locus Sequence Typing: rapid accumulation of genomic heterogeneity among clonal isolates of Campylobacter jejuni - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

BMC Evolutionary Biology

, 8:229

First Online: 08 August 2008Received: 13 March 2008Accepted: 08 August 2008


BackgroundMulti-Locus Sequence Typing MLST has emerged as a leading molecular typing method owing to its high ability to discriminate among bacterial isolates, the relative ease with which data acquisition and analysis can be standardized, and the high portability of the resulting sequence data. While MLST has been successfully applied to the study of the population structure for a number of different bacterial species, it has also provided compelling evidence for high rates of recombination in some species. We have analyzed a set of Campylobacter jejuni strains using MLST and Comparative Genomic Hybridization CGH on a full-genome microarray in order to determine whether recombination and high levels of genomic mosaicism adversely affect the inference of strain relationships based on the analysis of a restricted number of genetic loci.

ResultsOur results indicate that, in general, there is significant concordance between strain relationships established by MLST and those based on shared gene content as established by CGH. While MLST has significant predictive power with respect to overall genome similarity of isolates, we also found evidence for significant differences in genomic content among strains that would otherwise appear to be highly related based on their MLST profiles.

ConclusionThe extensive genomic mosaicism between closely related strains has important implications in the context of establishing strain to strain relationships because it suggests that the exact gene content of strains, and by extension their phenotype, is less likely to be -predicted- based on a small number of typing loci. This in turn suggests that a greater emphasis should be placed on analyzing genes of clinical interest as we forge ahead with the next generation of molecular typing methods.

AbbreviationsCGHcomparative genomic hybridization

HVhighly variable

HDhighly divergent

MDmoderately divergent

MLSTmulti-locus sequence typing

STsequence type

CCclonal complex

SLVsingle-locus variant

DLVdouble-locus variant

TLVtriple-locus variant

LRLog Ratio

SLRDsignificant Log Ratio difference

LOSlipo-oligosaccharide biosynthesis locus

FLflagellar biosynthesis locus

CPScapsular polysaccharide biosynthesis locus

RMtype I restriction-modification locus.

Electronic supplementary materialThe online version of this article doi:10.1186-1471-2148-8-229 contains supplementary material, which is available to authorized users.

Download fulltext PDF

Autor: Eduardo N Taboada - Joanne M MacKinnon - Christian C Luebbert - Victor PJ Gannon - John HE Nash - Kris Rahn


Documentos relacionados