Iron hydrogenase

Frenking G, Cremer D (1990) The Chemistry of the Nobles Gas Elements Helium, Neon, and Argon - Experimental Facts and Theoretical Predictions. 73 17-96 Frey M (1998) Nickel-Iron Hydrogenases Structural and Functional Properties. 90 97-126 Fricke B (1975) Superheavy Elements. 21 89-144... 

De Luca G, P de Philip, Z Dermoun, M Rouseet, A Vermeglio (2001) Reduction of Technetium (VII) by Desulfovibrio fructosovorans is mediated by the nickel-iron hydrogenase. Appl Environ Microbiol 67 468-475. 

Juszczak A, S Aono, MWW Adams (1991) The extremely thermophilic eubacterium Thermotoga maritima, contains a novel iron-hydrogenase whose cellular activity is dependent upon tungsten. J Biol Chem 266 13834-13841. 

Amara, P., Volbeda, A., Fontecilla-Camps, J. C., Field, M. J., 1999, A Hybrid Density Functional Theory/Mo-lecular Mechanics Study of Nickel-Iron Hydrogenase Investigation of the Active Site Redox States , J. Am. Chem. Soc., 121, 4468. 

L. Florin, A. Tsokoglou, T. Happe (2001) A novel type of iron hydrogenase in the green alga Scenedesmus obliquus is linked to the photosynthetic electron transport chain. J. Biol. Chem., 276 6125-6132... 

DS. Homer, B. Heil, T. Happe, TM. Embley (2002) Iron hydrogenases - ancient enzymes in modem eukaryotes. TrendsBiochem Sci., 27 148-153... 

Butt, J. N., Filipiak, M. and Hagen, W. R. (1997) Direct electrochemistry oi Megasphaera elsdenii iron hydrogenase. Definition of the enzymes catalytic operating potential and quantitation of the catalytic behaviour over a continuous potential range. Eur. J. Biochem., 245,116-22. 

Nicolet, Y., Piras, C., Legrand, P., Hatchikian, C. E. and Fontecilla-Camps, J. C. (1999) Desulfovibrio desulfuricans iron hydrogenase The structure shows unusual coordination to an active site Fe binuclear center. Structure Fold. Des., 7, 13-23. 

Sorgenfrei, O., Linder, D., Karas, M. and Klein, A. (1993a) A novel very small subunit of a selenium containing [nickel-iron] hydrogenase of Methanococcus voltae is postranslation-ally processed by cleavage at a defined position. Eur. J. Biochem., 213, 1355-8. 

Verhagen, M. F., ORourke, T. and Adams, M. W. (1999) The hyperthermophilic bacterium, Thermotoga maritime, contains an unusually complex iron-hydrogenase Amino acid sequence analyses versus biochemical characterization. Biochim. Biophys. Acta, 1412, 212-29. 

Volbeda, A., Charon, M.-H., Piras, C., Hatchikian, E. C., Frey, M. and Fontecilla-Camps, J. C. (1995) Crystal structure of the nickel-iron hydrogenase from Desulfovibrio gigas. Nature (London), 373, 580-7. 

Frey M. 1998. Nickel-iron hydrogenases structural and functional properties. Struct Bonding 90 98-126. 

Volbeda A, Charon M-H, Piras C, et al. 1995. Crystal structure of the nickel-iron hydrogenase from Desulfovibrio gigas. Nature 373 580-7. 

Each iron atom is terminally coordinated by one CO and one CN . The coordination of Fel is completed by the additional bridging cysteinyl sulfur. For Fe2, the sixth coordination site may be empty, as in the D. desulfuricans enzyme (Nicolet et al. 1999), or occupied by a solvent molecule, as observed in the C. pasteurianum enzyme (Peters et al. 1999). The assignment for the diatomic ligands is supported by infrared spectroscopic evidence (Pierik et al. 1998X and similar diatomic ligands have also been found for the corresponding binuclear [Ni-Fe] cluster of the nickel-iron hydrogenases (Volbeda et al. 1995). 

Adams MWW. 1990. The structure and mechanism of iron-hydrogenases. Biochim Biophys Acta 1020 115 5. 

Pierik AJ, Hagen WR, Redeker JS, et al. 1992. Redox properties of the iron-snlfnr clusters in activated iron-hydrogenase from Desulfovibrio vulgaris (Hildenbor-ough). Eur J Biochem 209 63-72. 

Figure 18.4. Proposed biocorrosion model for cathodic electron depolarization of mild steel by D. vulgaris Hildenborough. CM, cytoplasmic membrane HMC, high molecular weight cytochrome [Fe] Fl2ase, iron hydrogenase [NiFe] H2ase, nickel iron hydrogenase ETS, electron transport system.

Nickel-iron hydrogenases [NiFe] (Figure 8.2) are present in several bacteria. Their structure is known [22, 23] to be a heterodimeric protein formed by four subunits, three of which are small [Fe] and one contains the bimetallic active center consisting of a dimeric cluster formed by a six coordinated Fe linked to a pentacoordinated Ni (III) through two cysteine-S and a third ligand whose nature changes with the oxidation state of the metals in the reduced state it is a hydride, H, whereas in the oxidized state it may be either an oxo, 0, or a sulfide,... 

Horner DS, Heil , Happe T, Embley TM (2002) Iron hydrogenases - ancient enzymes in modern eukaryotes. Trends Biochem Sci 27 148-153 Hrdy I, Hirt RP, Dolezal P, Bardonova L, Foster PG, Tachezy J, Embley TM (2004) Trichomonas hydrogenosomes contain the NADH dehydrogenase module of mitochondrial complex I. Nature 432 618-622 Hurtgen MT (2003) Ancient oceans and oxygen. Nature 423 592-593 Javaux EJ, Knoll AH, Walter MR (2001) Morphological and ecological complexity in early eukaryotic ecosystems. Nature 412 66-69... 

Iron hydrogenase hydA Iron hydrogenase hydB + (D + (D + (Bui and Johnson 1996) (Bui and Johnson 1996)... 

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