The genome of Mycobacterium africanum West African 2 reveals a lineage-specific locus and genome erosion common to the M. tuberculosis complex.
PLoS Negl Trop Dis
; 6(2): e1552, 2012.
Article
en En
| MEDLINE
| ID: mdl-22389744
ABSTRACT
BACKGROUND:
M. africanum West African 2 constitutes an ancient lineage of the M. tuberculosis complex that commonly causes human tuberculosis in West Africa and has an attenuated phenotype relative to M. tuberculosis. METHODOLOGY/PRINCIPALFINDINGS:
In search of candidate genes underlying these differences, the genome of M. africanum West African 2 was sequenced using classical capillary sequencing techniques. Our findings reveal a unique sequence, RD900, that was independently lost during the evolution of two important lineages within the complex the "modern" M. tuberculosis group and the lineage leading to M. bovis. Closely related to M. bovis and other animal strains within the M. tuberculosis complex, M. africanum West African 2 shares an abundance of pseudogenes with M. bovis but also with M. africanum West African clade 1. Comparison with other strains of the M. tuberculosis complex revealed pseudogenes events in all the known lineages pointing toward ongoing genome erosion likely due to increased genetic drift and relaxed selection linked to serial transmission-bottlenecks and an intracellular lifestyle. CONCLUSIONS/SIGNIFICANCE:
The genomic differences identified between M. africanum West African 2 and the other strains of the Mycobacterium tuberculosis complex may explain its attenuated phenotype, and pave the way for targeted experiments to elucidate the phenotypic characteristic of M. africanum. Moreover, availability of the whole genome data allows for verification of conservation of targets used for the next generation of diagnostics and vaccines, in order to ensure similar efficacy in West Africa.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
ADN Bacteriano
/
Genoma Bacteriano
/
Mycobacterium
Tipo de estudio:
Prognostic_studies
Límite:
Adult
/
Animals
/
Humans
/
Male
País/Región como asunto:
Africa
Idioma:
En
Revista:
PLoS Negl Trop Dis
Asunto de la revista:
MEDICINA TROPICAL
Año:
2012
Tipo del documento:
Article
País de afiliación:
Reino Unido