Methanol dehydrogenase structure

M. Ghosh, C. Anthony, K. Harlos, M.G. Goodwin, and C. Blake, The refined structure of the quino-protein methanol dehydrogenase from Methylobacterium extorquens at 1.94A. Structure 3, 177—187 (1995). 

C. Anthony, M. Ghosh, and C.C. Blake, The structure and function of methanol dehydrogenase and related quinoproteins containing pyrrolo-quinoline quinone. Biochem. J. 304, 665-674 (1994). 

Evidence for a hydride transfer mechanism (Scheme 29) for the PQQ-dependent enzyme methanol dehydrogenase (MDH) was obtained by a theoretical analysis combined with an improved refinement of a 1.9 A resolution crystal structure of MDH from Methylophilus methylotrophus in the presence of CH3OH <2001PNA432>. The alternative mechanism proceeding via a hemiketal intermediate was discounted when the observed tetrahedral configuration of the C-5 atom of PQQ in that crystal structure was shown to be the C-5-reduced form of the cofactor 198, a precursor to the more common reduced form of PQQ 199. 

Figure 15-23 (A) Stereoscopic view of the H subunit of methanol dehydrogenase. Eight four-stranded antiparallel 3 sheets, labeled W1-W8, form the base of the subunit. Several helices and two additional P-sheet structures (labeled Px and Py) form a cap over the base. The PQQ is located in a funnel within the cap approximately on an eight-fold axis of pseudosymmetry. Courtesy of Xia et al.ii7 (B) Schematic view of the active site. W467 is parallel to the plane of PQQ. All hydrogen-bond interactions between PQQ and its surrounding atoms, except for the three water molecules, are indicated. Courtesy of White et al.ii8...

Cozier, G. E., and Anthony, C. (1995a). Structure of the quinoprotein glucose dehydrogenase of Escherichia coli modelled on that of methanol dehydrogenase from Methylobact-erium extorquens. Biochem. J., 312, 679-685. 

Ghosh, M., Anthony, C., Harlos, K., Goodwin, M. G., and Blake, C. (1995). The refined structure of the quinoprotein methanol dehydrogenase from Methylobacterium ex-torquens at 1.94 A. Structure, 3, 177-187. 

Different 2H-, 13C- and/or 15N isotopomers of L-serine, [(S)-2-amino-3-hydroxypro-panoic acid], 95, required for studies of aminoacid metabolism and for studies of peptide and protein structure and dynamics, have been biosynthesized stereoselectively84 using the serine-type methylotrophic bacterium, Methylobacteri extorquens AMI, which contains85 large amounts of the enzymes methanol dehydrogenase and hydroxymethyl-transferase (equation 39). 

This chapter will review the general features of the enzymology of methanol dehydrogenase, its structure as determined by X-ray crystallography, the properties of the prosthetic group (PQQ), the mechanism of its reduction by substrate, its oxidation by its specific cytochrome electron acceptor, and processes involved in its synthesis. 

Blake, C. C. F., Ghosh, M., Harlos, K., Avezoux, A., and Anthony, C., 1994, The active site of methanol dehydrogenase contains a disulphide bridge between adjacent cysteine residues. Nature, Structural Biology 1 1029105. 

Westerling J, Frank J, Duine JA (1979) The prosthetic group of methanol dehydrogenase from Hyphomicrobium X electron spin resonance evidence for a quinone structure. Biochem Biophys Res Commun 87 719-724... 

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