Activity was tested against substrates sampling different ground-state charges (from 0 to -2) and transition-state (TS) geometries (tetrahedral and trigonal-bipyramidal). The mini-cAMPase hydrolyses p -nitrophenyl phosphodiesters and phosphonates. The highest activity was observed for cAMP hydrolysis. The scissile bond is highlighted in blue. Cross symbols indicate no detectable activity. R indicates the p -nitrophenol leaving group.
