Mycobacterium and Leishmania: stowaways in the endosomal network.

Microbial pathogens have evolved to exploit a wide range of niches inside the vertebrate host cell. Both Leishmania and Mycobacterium species remain within vacuoles following phagocytosis by their host's macrophages. Leishmania survives in acidic, lysosomal compartments, whereas Mycobacterium species limit the maturation of their phagosomes into hydrolytic lysosomes. Recent advances in our appreciation of the biology of these pathogens is providing unique insights into the normal conversion of phagosomes into lysosomes.