title: Acid-dependent degradation of a [2Fe-2S] cluster by nitric oxide.
abstract: New types of degradation products of iron-sulfur clusters by nitric oxide (NO) have been identified in the acidic environment. In the absence of acid, NO reacts with (Et(4)N)(2)[Fe(2)S(2)Cl(4)] (1) to form a {Fe(NO)(2)}(9) dinitrosyliron complex, (Et(4)N)[Fe(NO)(2)Cl(2)] (2), wherein the bridging sulfides are oxidized to elemental sulfur by four electrons (2S(2-) → 2S(0) + 4e(-)). In contrast, the successive additions of NO and HCl to 1 result in the formation of a {Fe(NO)}(7) mononitrosyliron complex, (Et(4)N)[Fe(NO)Cl(3)] (3), along with elemental sulfur and hydrogen sulfide (H(2)S), which are the two-electron-oxidized products of the bridging sulfides (2S(2-) + 2H(+) → H(2)S + S(0) + 2e(-)). The results demonstrate that the acidic environment plays a significant role in controlling the chemistry of an iron-sulfur cluster with NO and imply how two important gaseous molecules, NO and H(2)S, can be interconnected through iron-sulfur clusters.
authors.affiliation: Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
authors.forename: Camly T
authors.initials: CT
authors.lastname: Tran
authors.forename: Eunsuk
authors.initials: E
authors.lastname: Kim
mesh_terms: D058085:Iron Compounds / Q000737:chemistry / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D013440:Sulfides / Q000737:chemistry / Q000378:metabolism*; D013455:Sulfur / Q000737:chemistry / Q000378:metabolism
chemical_list: D058085:Iron Compounds; D007506:Iron-Sulfur Proteins; D013440:Sulfides; D009569:Nitric Oxide; D013455:Sulfur