Capture of Ni II , Cu I and Zn II by thiolate sulfurs of an N 2 S 2 Ni complex: A role for a metallothiolate ligand in the acetyl-coenzyme A synthase active site

The metal binding affinity of an (N2S2)Ni bridging metallothiolate ligand (Zn2+ < Ni2+ < Cu+) gives precedent for the observed heterogeneity in ACS/CODH.