Catalytic mechanism of quinoprotein methanol dehydrogenase: A theoretical and x-ray crystallographic investigation.
Zheng, Y.J., Xia, Z.x., Chen, Z.w., Mathews, F.S., Bruice, T.C.(2001) Proc Natl Acad Sci U S A 98: 432-434
- PubMed: 11149955 
- DOI: https://doi.org/10.1073/pnas.98.2.432
- Primary Citation of Related Structures:  
1G72 - PubMed Abstract: 
The catalytic mechanism of the reductive half reaction of the quinoprotein methanol dehydrogenase (MDH) is believed to proceed either through a hemiketal intermediate or by direct transfer of a hydride ion from the substrate methyl group to the cofactor, pyrroloquinoline quinone (PQQ). A crystal structure of the enzyme-substrate complex of a similar quinoprotein, glucose dehydrogenase, has recently been reported that strongly favors the hydride transfer mechanism in that enzyme. A theoretical analysis and an improved refinement of the 1.9-A resolution crystal structure of MDH from Methylophilus methylotrophus W3A1 in the presence of methanol, reported earlier, indicates that the observed tetrahedral configuration of the C-5 atom of PQQ in that study represents the C-5-reduced form of the cofactor and lends support for a hydride transfer mechanism for MDH.
Organizational Affiliation: 
DuPont Agriculture Products, Stine-Haskell Research Center, Newark, DE 19714, USA.