Purity > 90% as determined by SDS-PAGE. MW: 99.9kDa. Full Length: 1-848aa. N-terminal 6xHis-tagged. Escherichia coli (strain K12). Catalyzes the formation of the second messenger cAMP from ATP. Its transcript is probably degraded by endoribonuclease LS (rnlA), decreasing cAMP levels and the negative regulator Crp-cAMP, which then induces its own transcription again.