Methylamine dehydrogenase complex

ELECTRON TRANSFER REACTIONS IN METHYLAMINE DEHYDROGENASE COMPLEXES... 

KA Gray, VL Davidson, DB Knaff. Complex formation between methylamine dehydrogenase and amicyanm from Paracocuus demtnficans. J Biol Chem 263 13987-13990, 1988. 

Conversion of methanol into formaldehyde by methanol dehydrogenase. A complex array of genes is involved in this oxidation and the dehydrogenase contains pyrroloquinoline quinone (PQQ) as a cofactor (references in Ramamoorthi and Lidstrom 1995). Details of its function must, however, differ from that of methylamine dehydrogenase that also contains a quinoprotein—tryptophan tryptophylquinone (TTQ). 

Metal-bound amino acid complexes, 206-209 Metal ions, in biological systems, 153—154 Methylamine dehydrogenase, 69—70 reaction diagram, 54/... 

Fig. 6. Electron transfer complex between methylamine dehydrogenase and amicyanin from Paracoccus dentrificans (PDB Accession Code 2MTA). The distance shown is between eN of the redox cofactor tryptophan tryptophylquinone of methylamine dehydrogenase and the eN of the His-95 ligand of amicyanin.

Methylamine Dehydrogenase Structure and Function of Electron Transfer Complexes... 

METHYLAMINE DEHYDROGENASE-AMICYANIN-CYTOCHROME c-551i COMPLEX... 

Chen, L., Durley, R., Mathews, F. S., and Davidson, V. L., 1994, Structure of an electron transfer complex Methylamine dehydrogenase, amicyanin and cytochrome c-551i. Science 264 86990. 

Davidson, V. L., and Jones, L. H., 1995, Complex formation with methylamine dehydrogenase affects the pathway of electron transfer from amicyanin to cytochrome c-551i. J. Biol. Chem. 270 23941A23943. 

Kumar, M. A., and Davidson, V. L., 1990, Chemical cross-linking study of complex formation between methylamine dehydrogenase and amicyanin from Paracoccus denitrificans. Biochemistry, 29 529995304. 

Three-dimensional structures. The TPQ-con-taining amine oxidase from E. coU is a dimer of 727-residue subunits with one molecule of TPQ at position 402 in each subunit. 7458 Methylamine dehydrogenase is also a large dimeric protein of two large 46.7-kDa subunits and two small 15.5-kDa subunits. Each large subunit contains a TTQ cofactor Reduced TTQ is reoxidized by the 12.5-kDa blue copper protein amicyanin. Crystal structures have been determined for complexes of methylamine dehydrogenase with amicyanin and of these two proteins with a third protein, a small bacterial cytochrome... 

Aromatic residues have been found in proteins at positions that probably enhance the electronic coupling in systems that have been selected by evolution for efficient ET. Examples are the tryptophan mediated reduction of quinone in the photosynthetic reaction center (31), the methylamine dehydrogenase (MADH) amicyanin system, where a Trp residue is placed at the interface between the two proteins (32), as well as the [cytochrome c peroxidase-cytochrome c] complex, where a Trp seems to have a similar function (33). 

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