Picomolar inhibition of beta-galactosidase (bovine liver) attributed to loop closure

by Pickens, Jessica B.; Wang, Feng; Striegler, Susanne

In an effort to examine similarities in the active sites of glycosidases within the GH35 family, we performed a structure-activity-relationship study using our recently described library of galactonoamidines. The kinetic evaluation based on UV/Vis spectroscopy disclosed inhibition of beta-galactosidase (bovine liver) in the picomolar concentration range indicating significantly higher inhibitor affinity than previously determined for beta-galactosidase (A. oryzae). Possible alterations in the secondary protein structure or folding were excluded after further examination of the inhibitor binding using CD spectroscopy. Molecular dynamics studies suggested loop closing interactions as a rationale for the disparity of the active sites in the beta-galactosidases under investigation.

Journal
Bioorganic and Medicinal Chemistry
Volume
25
Issue
20
Year
2017
Start Page
5194-5202
URL
https://dx.doi.org/10.1016/j.bmc.2017.07.020
ISBN/ISSN
1464-3391; 0968-0896
DOI
10.1016/j.bmc.2017.07.020