<p>Aldose 1-epimerase (<db_xref db="EC" dbkey="5.1.3.3"/>) (mutarotase) is the enzyme responsible for the anomeric interconversion of D-glucose and other aldoses between their alpha- and beta-forms. The sequence of mutarotase from two bacteria, <taxon tax_id="471">Acinetobacter calcoaceticus</taxon> and <taxon tax_id="1308">Streptococcus thermophilus</taxon> is available [<cite idref="PUB00002113"/>]. It has also been shown that, on the basis of extensive sequence similarities, a mutarotase domain seems to be present in the C-terminal half of the fungal GAL10 protein that encodes, in the N-terminal part, UDP-glucose 4-epimerase. The best conserved region in the sequence of mutarotase is cantered around a conserved histidine residue which may be involved in the catalytic mechanism.</p><p> Galactose mutarotases (D-galactose 1-epimerase) participate in the Leloir pathway for galactose/glucose interconversion. Genes encoding the proteins found in this entry are found clustered with genes encoding other enzymes of the Leloir pathway. These proteins belong to the aldose 1-epimerase family. However, the aldose 1-epimerase itself (<db_xref db="EC" dbkey="5.1.3.3"/>) has a relatively broad specificity and can utilise D-glucose, L-arabinose, D-xylose, D-galactose, maltose and lactose. The restricted genomic context of the genes suggests members should act primarily on D-galactose.</p> Aldose 1-epimerase, bacterial