InterPro: IPR000274 Adenylate cyclase, class-I

Adenylate cyclase is the enzyme responsible for the synthesis of cAMP from ATP. From sequence data, it has been proposed that there are three different classes of adenylate cyclases [1]. Class I cyclases are found in enterobacteria and related Gram-negative bacteria. They are proteins of about 850 residues that consist of two functional domains: a N-terminal catalytic domain and a C-terminal regulatory domain. There are two highly conserved regions, the first one is located in the catalytic domain and the second one in the regulatory domain. The second signature includes a conserved histidine which could be phosphorylated by a PTS system IIA enzyme, thus leading to the activation of the cyclase.