Zoekopdracht: subjects: "Health and Nutrition"
|Titel||Conservation of the S10-spc-a Locus within otherwise highly plastic genomes provides phylogenetic insight into the Genus Leptospira|
|Auteurs||B. Victoria, A. Ahmed, R.L. Zuerner, N. Ahmed, D.M. Bulach, J. Quinteiro, R.A. Hartskeerl|
|Organisatie||KIT - Royal Tropical Institute|
|Onderwerp||Health and Nutrition|
|Samenvatting||S10-spc-a is a 17.5 kb cluster of 32 genes encoding ribosomal proteins. This locus has an unusual composition and|
organization in Leptospira interrogans. We demonstrate the highly conserved nature of this region among diverse Leptospira
and show its utility as a phylogenetically informative region. Comparative analyses were performed by PCR using primer
sets covering the whole locus. Correctly sized fragments were obtained by PCR from all L. interrogans strains tested for each
primer set indicating that this locus is well conserved in this species. Few differences were detected in amplification profiles
between different pathogenic species, indicating that the S10-spc-a locus is conserved among pathogenic Leptospira. In
contrast, PCR analysis of this locus using DNA from saprophytic Leptospira species and species with an intermediate
pathogenic capacity generated varied results. Sequence alignment of the S10-spc-a locus from two pathogenic species, L.
interrogans and L. borgpetersenii, with the corresponding locus from the saprophyte L. biflexa serovar Patoc showed that
genetic organization of this locus is well conserved within Leptospira. Multilocus sequence typing (MLST) of four conserved
regions resulted in the construction of well-defined phylogenetic trees that help resolve questions about the
interrelationships of pathogenic Leptospira. Based on the results of secY sequence analysis, we found that reliable species
identification of pathogenic Leptospira is possible by comparative analysis of a 245 bp region commonly used as a target for
diagnostic PCR for leptospirosis. Comparative analysis of Leptospira strains revealed that strain H6 previously classified as L.
inadai actually belongs to the pathogenic species L. interrogans and that L. meyeri strain ICF phylogenetically co-localized
with the pathogenic clusters. These findings demonstrate that the S10-spc-a locus is highly conserved throughout the genus
and may be more useful in comparing evolution of the genus than loci studied previously.
|Rechten||© 2008 Victoria et al. This work is licensed under a Creative Commons Attribution license|