Attenuation of Virulence by Disruption of the Mycobacterium tuberculosis erp Gene

Abstract
The virulence of the mycobacteria that cause tuberculosis depends on their ability to multiply in mammalian hosts. Disruption of the bacterial erp gene, which encodes the exported repetitive protein, impaired multiplication of M. tuberculosis andM. bovis Bacille Calmette-Guérin in cultured macrophages and mice. Reintroduction of erp into the mutants restored their ability to multiply. These results indicate thaterp contributes to the virulence of M. tuberculosis.