| Ps-CPG2 | E. coli AbgA homolog | E. coli AbgB homolog |
| Zinc1/2*: Asp (D141) | His(H146); Asp (D147) | His (H111) |
| Zinc1: Glu (E176) | Glu (E183) | Glu (E146) |
| Zinc1: His(H385) | His (H406) | Gly (G409) |
| Zinc2: Glu (E200) | Thr(T205) | His (H171) |
| Zinc2: His (H112) | Asp (D116) | Glu (E81) |