Kinetic scheme of ATP inhibition of sGC (E) by two independent sites. Equilibria scheme for an enzyme (E) with one active site and one regulating allosteric site, binding to substrate (GTP) and inhibitor (ATP). Binding of GTP to the active site composes an active complex (EGTP) producing product (cGMP). Ks, Kic, and Kia are the dissociation constants of the EGTP, EATP, and ATPE complexes.