<p>The UDP-glucose/GDP-mannose dehydrogenases are a small group of enzymes which possesses the ability to catalyse the NAD-dependent 2-fold oxidation of an alcohol to an acid without the release of an aldehyde intermediate [<cite idref="PUB00002546"/>, <cite idref="PUB00003005"/>].</p><p>The enzymes have a wide range of functions. In plants UDP-glucose dehydrogenase, <db_xref db="EC" dbkey="1.1.1.22"/>, is an important enzyme in the synthesis of hemicellulose and pectin [<cite idref="PUB00009417"/>], which are the components of newly formed cell walls; while in zebrafish UDP-glucose dehydrogenase is required for cardiac valve formation [<cite idref="PUB00009418"/>]. In <taxon tax_id="339">Xanthomonas campestris</taxon>, a plant pathogen, UDP-glucose dehydrogenase is required for virulence [<cite idref="PUB00009419"/>]. </p><p>GDP-mannose dehydrogenase, <db_xref db="EC" dbkey="1.1.1.132"/>, catalyses the formation of GDP-mannuronic acid, which is the monomeric unit from which the exopolysaccharide alginate is formed. Alginate is secreted by a number of bacteria, which include <taxon tax_id="287">Pseudomonas aeruginosa</taxon> and <taxon tax_id="354">Azotobacter vinelandii</taxon>. In P. aeruginosa, alginate is believed to play an important role in the bacteria's resistance to antibiotics and the host immune response [<cite idref="PUB00009420"/>], while in A. vinelandii it is essential for the encystment process [<cite idref="PUB00009421"/>].</p><p>This entry represents the N-terminal NAD(+)-binding domain. Structural studies indicate that this domain forms an alpha-beta structure containing the six-stranded parallel beta sheet characteristic of the dinucleotide binding Rossman fold [<cite idref="PUB00028366"/>, <cite idref="PUB00027324"/>].</p>