Crystal structure-guided design of berberine-based novel chitinase inhibitors.

ABSTRACT: Glycoside hydrolase family 18 (GH18) chitinases play an important role in various organisms ranging from bacteria to mammals. Chitinase inhibitors have potential applications as pesticides, fungicides, and anti-asthmatics. Berberine, a plant-derived isoquinoline alkaloid, was previously reported to inhibit against various GH18 chitinases with only moderate K _i values ranging between 20 and 70 μM. In this report, we present for the first time the berberine-complexed crystal structure of SmChiB, a model GH18 chitinase from the bacterium Serratia marcescens. Based on the berberine-binding mode, a hydrophobic cavity-based optimisation strategy was developed to increase their inhibitory activity. A series of berberine derivatives were designed and synthesised, and their inhibitory activities against GH18 chitinases were evaluated. The compound 4c showed 80-fold-elevated inhibitory activity against SmChiB and the human chitinase hAMCase with K _i values at the sub-micromolar level. The mechanism of improved inhibitory activities was proposed. This work provides a new strategy for developing novel chitinase inhibitors.

SUBMITTER: Chen L 

PROVIDER: S-EPMC7655067 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature