Fig. 1. The catalytic Post-Albers cycle. Schematic representation of the catalytic Post-Albers cycle in P-Type ATPases exemplified for a Zn(ii)-pump. The transmembrane domain featuring the transmembrane high-affinity M²⁺ (M²⁺ = Zn²⁺, Cd²⁺, Hg²⁺, and Pb²⁺) binding-site is shown in grey color. The A-, P-, and N-domains are shown in yellow, blue and red, respectively. The two N-terminal helices (TM-A and -B) characteristic of P_1B-type ATPases, the soluble N-terminal metal binding domain and His-rich terminal tail are colored in blue (based on CmZntA topology). Movements of the corresponding domains based on the catalytic cycle of SERCA are indicated by colored arrows.