Mycobacterium Tuberculosis Signaling via c-AMP

Adelynate cyclases (ACs), which catalyze synthesis of cAMP from ATP and yield pyrophosphate as a by-product, can be classified into four different classes according to their common features: Class I cyclases, related to enterobacterial adenylate cyclases; Class II, toxic adenylate cyclases isolated from bacterial pathogens; Class III, a large and probably ancient class that comprises cyclases from both eukaryotes and prokaryotes and is strongly related to guanylate cyclases; and Class IV, with mainly one example that differs entirely from all other classes (McCue et al., 2000).