Turning the Tuberculosis Bacterium Lineage on its Head

Courtesy of Roland Brosch

The regions absent from the attenuated vaccine strain Mycobacterium bovis BCG Pasteur relative to the M. tuberculosis H37Rv genome are shown as gray boxes. Open reading frames (ORFs) are represented as pointed boxes showing the direction of transcription, with colors reflecting the functional classification of the ORFs similar to the ones on the TubercuList server http://genolist.pasteur.fr/TubercuList/.

Not long after the genome sequence of Mycobacterium tuberculosis was released in 1998,¹ it began paying scientific dividends. This issue's Hot Papers offered insight into how Mycobacterium changed and evolved. One paper worked at the "micro" timescale, examining genomic differences among laboratory and clinical strains of M. tuberculosis. The other, looking on a "macro" timescale, reported a novel hypothesis for the evolutionary relationship of several Mycobacterium lineages.

Surprising many, Institut Pasteur scientist Roland Brosch and colleagues overturned a widely accepted theory about how M. tuberculosis had evolved.2 Skeletal deformities in ...