摘要 |
Macromolecular compositions are provided which find use as glycosidase substrates, particularly where steric modulation of enzyme activity is involved. The compositions have a macromolecular hub to which is linked by means of a spacer arm a chromophore, which in turn is bonded to a sugar by an enzymatically labile glycosidyl linkage. The chromophore is chosen so as to undergo a substantial change in its chromophoric properties upon cleavage of the glycosidyl linkage. The enzyme activity can be determined spectrophotometrically due to the change in the absorptive or fluorescent properties of the chromophore upon cleavage of the glycosidyl linkage. Varying turnover rates for the enzyme are observed depending upon the nature of the macromolecular hub, the spacer arm, and the chromophore. |