Trehalose-phosphatases <db_xref db="EC" dbkey="3.1.3.12"/> catalyse the de-phosphorylation of trehalose-6-phosphate to trehalose and orthophosphate. Trehalose is a common disaccharide of bacteria, fungi and invertebrates that appears to play a major role in desiccation tolerance. A pathway for trehalose biosynthesis may also exist in plants [<cite idref="PUB00008121"/>]. The trehalose-phosphatase signature is found in the C terminus of trehalose-6-phosphate synthase <db_xref db="EC" dbkey="2.4.1.15"/> adjacent to the trehalose-6-phosphate synthase domain (see <db_xref db="INTERPRO" dbkey="IPR001830"/>). It would appear that the two equivalent genes in the <taxon tax_id="562">Escherichia coli</taxon> otsBA operon: otsA, the trehalose-6-phosphate synthase and otsB, trehalose-phosphatase (this family) have undergone gene fusion in most eukaryotes [<cite idref="PUB00001848"/>]. Trehalose-phosphatase