Alignment of amino acid sequences of various
[NiFe] hydrogenase small subunits around the three cysteine ligands
to the [3Fe-4S] center. The sequences were taken from refs. 8
(D. gigas [NiFe] hydrogenase, D. g.),
18 (D. fructosovorans, D. f.), 21 (D.
vulgaris Miyazaki F, D. v.), 22
(Rhodobacter capsulatus, R. c.), 23
(Bradirhizobium japonicum, B. j.), and 8 (D.
baculatum, Dm. b.). The cysteine cluster ligands and the
conserved proline residue corresponding to position 239 in D.
gigas enzyme are shown in bold.