Crystal structure of formate dehydrogenase H: catalysis involving Mo, molybdopterin, selenocysteine, and an Fe4S4 cluster.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 9036855.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Formate dehydrogenase H from Escherichia coli contains selenocysteine (SeCys), molybdenum, two molybdopterin guanine dinucleotide (MGD) cofactors, and an Fe4S4 cluster at the active site and catalyzes the two-electron oxidation of formate to carbon dioxide. The crystal structures of the oxidized [Mo(VI), Fe4S4(ox)] form of formate dehydrogenase H (with and without bound inhibitor) and the reduced [Mo(IV), Fe4S4(red)] form have been determined, revealing a four-domain alphabeta structure with the molybdenum directly coordinated to selenium and both MGD cofactors. These structures suggest a reaction mechanism that directly involves SeCys140 and His141 in proton abstraction and the molybdenum, molybdopterin, Lys44, and the Fe4S4 cluster in electron transfer.
Medical subject headings
- Ferrous Compounds
- Formate Dehydrogenases
- Formates
- Hydrogenase
- Multienzyme Complexes
- Protein Conformation