GDP-mannose 4,6-dehydratase

In enzymology, a GDP-mannose 4,6-dehydratase is an mannosyltransferase enzyme that catalyzes the chemical reaction


 * GDP-mannose $$\rightleftharpoons$$ GDP-4-dehydro-6-deoxy-D-mannose + H2O

Hence, this enzyme has one substrate, GDP-mannose, and two products, GDP-4-dehydro-6-deoxy-D-mannose and H2O.

This enzyme belongs to the family of lyases, specifically the hydro-lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is GDP-mannose 4,6-hydro-lyase (GDP-4-dehydro-6-deoxy-D-mannose-forming). Other names in common use include guanosine 5'-diphosphate-D-mannose oxidoreductase, guanosine diphosphomannose oxidoreductase, guanosine diphosphomannose 4,6-dehydratase, GDP-D-mannose dehydratase, GDP-D-mannose 4,6-dehydratase, Gmd, and GDP-mannose 4,6-hydro-lyase. This enzyme participates in fructose and mannose metabolism. It employs one cofactor, NAD+.

Structural studies
As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes, , , , and.