Effect of phosphate analogues on the digestion pattern of T. maritima CopA. SDS–PAGE was performed as described in Experimental Procedures. Purified CopA (0.5 mg/mL) was incubated with 0.5 mg/mL papain at 50 °C for 30 min in the presence of 1 mM BCS (no copper added), in the absence or presence of 2 mM ATP, or following preincubation with 0.2 mM MgF, 0.2 mM AlF, 0.2 mM BeF, or 0.2 mM Be(NO3)2.