REAL TIME METHYLUMBELLIFERONE-BASED ASSAY

摘要

A method is provided for determining the activity of an enzyme which releases methylumbelliferone (MU) from an MU-containing substrate wherein the enzyme has a pH optimum below the pKa of MU comprising: contacting a sample suspected of containing the enzyme with the MU- containing substrate at a pH suitable for activity of the enzyme to allow release of MU by the enzyme; contacting the sample with light of a wavelength in the range of about 310nm to about 350nm; determining fluorescence produced by the released MU, thereby determining the activity o f the enzyme. This real time method provides improved diagnostic methods, for example for diseases associated with an abnormal level of activity of a glycosidase. The real time assay also can be used to screen compounds for their ability to modulate enzyme activity using MU-containing substrates.