Mycobacterium bovis Requires P27 (LprG) To Arrest Phagosome Maturation and Replicate within Bovine Macrophages.

causes tuberculosis in a wide variety of mammals, with strong tropism for cattle and eventually humans. P27, also called LprG, is among the proteins involved in the mechanisms of the virulence and persistence of and Here, we describe a novel function of P27 in the interaction of with its natural host cell, the bovine macrophage. We found that a deletion in the operon impairs the replication of in bovine macrophages. Importantly, we show for the first time that arrests phagosome maturation in a process that depends on P27. This effect is P27 specific since complementation with wild-type but not fully restored the wild-type phenotype of the mutant strain; this indicates that P55 plays no important role during the early events of infection. In addition, we also showed that the presence of P27 from decreases the association of LAMP-3 with bead phagosomes, indicating that P27 itself blocks phagosome-lysosome fusion by modulating the traffic machinery in the cell host.