Trehalose (1-alpha-D-glucopyranosyl alpha-D-glucopyranoside) is widely distributed in nature, being the storage disaccharide of fungi and the blood sugar of insects. Trehalase (EC 3.2.1.28) is an intrinsic glycoprotein of the small intestine and renal brush border membranes that hydrolyzes trehalose to 2 glucose molecules.

The deduced 583-amino acid protein has a calculated molecular mass of 66.6 kD. It has an N-terminal signal peptide, 5 potential N-glycosylation sites, and a C-terminal hydrophobic region for glycosylphosphatidylinositol (GPI) attachment. Northern blot analysis detected a 2.0-kb transcript mainly in kidney, liver, and small intestine.The trehalase signature sequence from amino acids 162 to 175 of mouse Treh shares 100% identity with the corresponding region in human TREH.