Discovery of a cAMP deaminase that quenches cyclic AMP-dependent regulation.

ABSTRACT: An enzyme of unknown function within the amidohydrolase superfamily was discovered to catalyze the hydrolysis of the universal second messenger, cyclic-3',5'-adenosine monophosphate (cAMP). The enzyme, which we have named CadD, is encoded by the human pathogenic bacterium Leptospira interrogans. Although CadD is annotated as an adenosine deaminase, the protein specifically deaminates cAMP to cyclic-3',5'-inosine monophosphate (cIMP) with a kcat/Km of 2.7 ± 0.4 × 10(5) M(-1) s(-1) and has no activity on adenosine, adenine, or 5'-adenosine monophosphate (AMP). This is the first identification of a deaminase specific for cAMP. Expression of CadD in Escherichia coli mimics the loss of adenylate cyclase in that it blocks growth on carbon sources that require the cAMP-CRP transcriptional activat

SUBMITTER: Goble AM 

PROVIDER: S-EPMC3880142 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature