Interrelation of Ca and PE_PGRS proteins during pathogenesis.

In today's era tuberculosis is a major threat to human population. The lethality of this disease is caused by very efficiently thrived bacteria . Ca plays crucial role in maintenance of cellular homeostasis. Bacilli survival in human alveolar macrophages majorly depends on disruption in Ca signaling. Bacilli sustainability in phagosome lies in the interruption of phagolysosomal fusion, which is possible because of low intracellular Ca concentration. Bacilli contain various Ca binding proteins which help in regulation of Ca signaling for its own benefit. For the survival of pathogen, it requires alteration in normal Ca concentration in healthy cell. In this review we aim to find the various Ca binding domains which are present in several Ca binding proteins of and variety of roles played by Ca to survive bacilli within host cell. This manuscript emphasizes the Ca binding domains present in PE_PGRS group of gene family and their functionality in survival and pathogenesis.