https://www.ncbi.nlm.nih.gov/Structure/pdb/3MYR
3MYR: Crystal structure of [NiFe] hydrogenase from Allochromatium vinosum in its Ni-A state
Hydrogenase (NiFe) small subunit HydANickel-dependent hydrogenase large subunitCHLORIDE IONFE3-S4 CLUSTERIMIDAZOLEIRON/SULFUR CLUSTERMAGNESIUM IONNI-FE...