FIG. 2.

Sequence comparisons with DSR from B. wadsworthia RZATAU. (A) Amino acid sequences derived from dsrB (upper line) aligned with those of DsrB from D. vulgaris (lower line). The amino acid sequence positions are indicated in the margins. Highly conserved cysteine residues proposed to coordinate siroheme-[4Fe-4S] binding (9) are indicated by boxes. Amino acids which do not show any homologies are in boldface. (B) Alignment of amino acids 405 to 483 of DsrB from B. wadsworthia DSR (Bw), with DsrD from D. vulgaris (Dv), Desulfotomaculum thermocisternum (Dt), A. fulgidus (Af), and A. profundus (Ap). Conserved lysine and arginine residues are indicated by boxes; a conserved stretch of eight amino acids is shown in boldface. ∗, positions with a conserved residue; :, positions with a conservative replacement.