Refers to sulfido ligands, e.g., the bridging ligands in iron-sulfur proteins, which are released as
H2S at acid pH.
See also: ferredoxin
Source:
PAC, 1997, 69, 1251. 'Glossary of terms used in bioinorganic chemistry (IUPAC Recommendations 1997)' on page 1254 (https://doi.org/10.1351/pac199769061251)