Structure of a hyperthermophilic tungstopterin enzyme, aldehyde ferredoxin oxidoreductase.Chan, M.K., Mukund, S., Kletzin, A., Adams, M.W., Rees, D.C.
(1995) Science 267: 1463-1469
- PubMed: 7878465
- PubMed Abstract:
- Molecular Characterization of the Genes Encoding Two Tungsten-Containing Enzymes from Hyperthermophilic Archaea: Aldehyde Ferredoxin Oxidoreductase from Pyrococcus Furiosus and Formaldehyde Ferredoxin Oxidoreductase from Thermococcus Litoralis
Kletzin, A.,Mukund, S.,Kelley-Crouse, T.L.,Chan, M.K.,Rees, D.C.,Adams, M.W.W.
() TO BE PUBLISHED --: --
The crystal structure of the tungsten-containing aldehyde ferredoxin oxidoreductase (AOR) from Pyrococcus furiosus, a hyperthermophilic archaeon (formerly archaebacterium) that grows optimally at 100 degrees C, has been determined at 2.3 angstrom res ...
The crystal structure of the tungsten-containing aldehyde ferredoxin oxidoreductase (AOR) from Pyrococcus furiosus, a hyperthermophilic archaeon (formerly archaebacterium) that grows optimally at 100 degrees C, has been determined at 2.3 angstrom resolution by means of multiple isomorphous replacement and multiple crystal form averaging. AOR consists of two identical subunits, each containing an Fe4S4 cluster and a molybdopterin-based tungsten cofactor that is analogous to the molybdenum cofactor found in a large class of oxotransferases. Whereas the general features of the tungsten coordination in this cofactor were consistent with a previously proposed structure, each AOR subunit unexpectedly contained two molybdopterin molecules that coordinate a tungsten by a total of four sulfur ligands, and the pterin system was modified by an intramolecular cyclization that generated a three-ringed structure. In comparison to other proteins, the hyperthermophilic enzyme AOR has a relatively small solvent-exposed surface area, and a relatively large number of both ion pairs and buried atoms. These properties may contribute to the extreme thermostability of this enzyme.
Division of Chemistry and Chemical Engineering, Pasadena, CA 91125.