| Content Provider |
World Health Organization (WHO)-Global Index Medicus |
| Author |
Mcternan, Patrick M. Yang, Qingyuan Vaccaro, Brian J. Hura, Greg L. Wu, Chang-hao Tainer, John A. Lancaster, W. Andrew Adams, Michael W. W. Chandrayan, Sanjeev K. Fu, Dax |
| Description |
Author Affiliation: McTernan PM ( From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-7229.); Chandrayan SK ( From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-7229.); Wu CH ( From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-7229.); Vaccaro BJ ( From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-7229.); Lancaster WA ( From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-7229.); Yang Q ( the Department of Physiology, John Hopkins University School of Medicine, Baltimore, Maryland 21205, and.); Fu D ( the Department of Physiology, John Hopkins University School of Medicine, Baltimore, Maryland 21205, and.); Hura GL ( the Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720.); Tainer JA ( the Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720.); Adams MW ( From the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-7229, adams@bmb.uga.edu.) |
| Abstract |
The archaeon Pyrococcus furiosus grows optimally at 100 °C by converting carbohydrates to acetate, CO2, and H2, obtaining energy from a respiratory membrane-bound hydrogenase (MBH). This conserves energy by coupling H2 production to oxidation of reduced ferredoxin with generation of a sodium ion gradient. MBH is encoded by a 14-gene operon with both hydrogenase and Na(+)/H(+) antiporter modules. Herein a His-tagged MBH was expressed in P. furiosus and the detergent-solubilized complex purified under anaerobic conditions by affinity chromatography. Purified MBH contains all 14 subunits by electrophoretic analysis (13 subunits were also identified by mass spectrometry) and had a measured iron:nickel ratio of 15:1, resembling the predicted value of 13:1. The as-purified enzyme exhibited a rhombic EPR signal characteristic of the ready nickel-boron state. The purified and membrane-bound forms of MBH both preferentially evolved H2 with the physiological donor (reduced ferredoxin) as well as with standard dyes. The O2 sensitivities of the two forms were similar (half-lives of â ¼ 15 h in air), but the purified enzyme was more thermolabile (half-lives at 90 °C of 1 and 25 h, respectively). Structural analysis of purified MBH by small angle x-ray scattering indicated a Z-shaped structure with a mass of 310 kDa, resembling the predicted value (298 kDa). The angle x-ray scattering analyses reinforce and extend the conserved sequence relationships of group 4 enzymes and complex I (NADH quinone oxidoreductase). This is the first report on the properties of a solubilized form of an intact respiratory MBH complex that is proposed to evolve H2 and pump Na(+) ions. |
| ISSN |
00219258 |
| e-ISSN |
1083351X |
| Journal |
Journal of Biological Chemistry |
| Issue Number |
28 |
| Volume Number |
289 |
| Language |
English |
| Publisher |
American Society for Biochemistry and Molecular Biology (United States) |
| Publisher Date |
2014-07-11 |
| Publisher Place |
United States |
| Access Restriction |
Open |
| Subject Keyword |
Archaeal Proteins Chemistry Cell Membrane Enzymology Hydrogenase Pyrococcus Furiosus Genetics Metabolism Catalytic Domain Crystallography, X-Ray Electron Transport Complex I Protein Structure, Quaternary Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Biochemistry Molecular Biology |
| Content Type |
Text |
| Resource Type |
Article |
| Subject |
Cell Biology Biochemistry Molecular Biology |
