We purified an acid trehalase (EC 188.8.131.52, α,α′-trehalose glucohydrolase) from an acidophilic bacterium, Acidobacterium capsulatum. The enzyme was homogeneous based on polyacrylamide gel electrophoresis, and was composed of a single polypeptide chain with a molecular mass of 57 kDa. Maximum trehalase activity was observed at pH 2.5. The acid trehalase exhibited an apparent Km of 1.0 mM for trehalose at 30°C and pH 3.0. The trehalase was located in the periplasmic space. The activity of the enzyme was activated by 1.0 mM MnCl2 or CoCl2, and inhibited by 1.0 mM PbCl2, HgCl2, NiCl2, p-chloromercuribenzoate, N-ethylmaleimide, monoiodoacetate, or EDTA. The enzyme showed high specificity for trehalose. It was found that an equimolar mixture of α-D-glucose and β-D-glucose was formed on hydrolysis of trehalose by the trehalase.
- Acid trehalase
- Acidobacterium capsulatum
- Enzyme purification
ASJC Scopus subject areas
- Applied Microbiology and Biotechnology