Methane monooxygenase components

Wallar, B. J. Lipscomb, J. D. Methane monooxygenase component B mutants alter the kinetics of steps throughout the catalytic cycle. Biochemistry 2001, 40(7), 2220-2233. 

Chang, S-L., Wallar, B.J., Lipscomb, J.D., and Mayo, K.H. (2001) Residues in Methylosinus trichosporium OB3b methane monooxygenase component B involved in molecular interactions with reduced- and oxidized-hydroxylase component A role for the N-terminus, Biochemistry 40, 9539-9551. 

Cytochrome P450 and soluble methane monooxygenase components and general enzyme characteristics... 

H.-C. Tsien and R. S. Hanson. Soluble methane monooxygenase component B gene probe for identification of methanotrophs that rapidly degrade trichloroethylene. Appl. Environ. Microbiol., 58 953 (1992). 

Froland WA, Andersson KK, Lee SK, Liu Y, Lipscomb JD. 1992. Methane monooxygenase component B and reductase alter the regioselectivity of the hydroxylase component-catalyzed reactions a novel role for protein-protein interactions in an oxygenase mechanism. JBiol Chem 267 17588-17597. 

Fox BG, Wa Froland, JE Dege, JD Lipscomb (1989) Methane monooxygenase from Methylosinus trichospo-rium OB3b. Purification and properties of a three-component system with a high specific activity from a type II methanotroph. J Biol Chem 264 10023-10033. 

STUDIES OF THE SOLUBLE METHANE MONOOXYGENASE PROTEIN SYSTEM STRUCTURE, COMPONENT INTERACTIONS, AND HYDROXYLATION MECHANISM... 

Figure 1. Characteristic EPR signals of Fe(II)Fe(III) sites in semimethemerythrinj (a), semimethemerythrinQ (b), reduced uteroferrin (c), reduced uteroferrin-molybdate complex (d), reduced bovine spleen purple acid phosphatase (e), reduced component A of methane monooxygenase (f). (Reproduced with permission from ref. 26. Copyright 1987 Elsevier.)...

The multiprotein complex methane monooxygenase (MMO) serves meth-anotrophs to convert methane to methanol. It can be either soluble (sMMO) or membrane bound ( particulate , pMMO) and it typically consists of three components, a reductase (MMOR), a component termed protein B (MMOB) and a hydroxylase denoted MMOH. The nature of the metal cofactors in the latter component are reasonably well understood for sMMO as will be discussed in the non-heme iron section. For the pMMO of Methylococcus capsulatus an obligate requirement for copper was shown. As reported in reference 1 a trinuclear Cu(II) cluster was discussed128 but the number and coordination of coppers still is a matter of continuing investigation since then. 

Studies of the Soluble Methane Monooxygenase Protein System Structure, Component Interactions, and Hydroxylation Mechanism Katherine E. Liu and Stephen J. Lippard... 

G. T. Gassner and S. J. Lippard, Component interactions in the soluble methane monooxygenase system, Biochem. 38, 12768-12785 (1999). 

Kopp, D.A., Gassner, George T., Blazyk, J.L., and Lippard, S.J. (2001) Electron-transfer reactions of the reductase component of soluble methane monooxygenase from Methylococcus capsulatus (Bath). 

Liu, K.E., Valentine, A.M., Wang, D., Huynh, B.H. Edmondson, D.E. Salifoglou, A. Lippard, SJ. (1995) Kinetic and spectroscopic characterization of intermediates and component interactions in reactions of methane monooxygenase from Methylococcus capsulatus (Bath), J. Am. Chem. Soc. 117, 10174-10185. 

FIGURE 1. Reaction and protein components of the soluble form of methane monooxygenase. 

Andersson, K. K., Eroland, W. A., Lee, S.-K., and Lipscomb, J. D., 1991, Dioxygen independent oxygenation of hydrocarbons by methane monooxygenase hydroxylase component. New J. Chem. 15 411n415. 

Davydov, A., Davydov, R., Gr%oslund, A., Lipscomb, J. D., and Andersson, K. K., 1997, Radiolytic reduction of methane monooxygenase dinuclear iron cluster At 77K6EPR evidence for conformational change upon reduction or binding of component B to the diferric state, J. Biol. Chem. 272 702267026. 

Fox, B. G., and Lipscomb, J. D., 1988, Purification of a high specific activity methane monooxygenase hydroxylase component from a type II methanotroph, Biochem. Biophys. Res. Commun. 154 165nl70. 

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