[2] The reaction involves the small protein DsrC, which is present in all the organisms that contain dissimilatory sulfite reductase.
[3] During the process an intramolecular trisulfide is formed between two L-cysteine residues of DsrC and the sulfur atom from sulfite.
[4] This trisulfide can be reduced by a number of proteins including DsrK and TcmB.
[5] Reaction in organisms performing dissimilatory sulfate reduction: Reaction in organisms performing sulfur oxidation: The systematic name of this enzyme class is hydrogen-sulfide:[DsrC sulfur-carrier protein],acceptor oxidoreductase.
This enzyme is different from EC 1.8.1.2, assimilatory sulfite reductase (NADPH), and EC 1.8.7.1, assimilatory sulfite reductase (ferredoxin), which are involved in sulfate assimilation.