Are Enzymes Sensitive to the Multivalent Effect? Emerging Evidence with Glycosidases

The multivalent effect in glycosidase inhibition is rapidly emerging as a hot topic of the research. In the last five years, several iminosugar-based inhibitors showed remarkable multivalent effects towards specific glycosidases, thus demonstrating that the concept of multivalency goes far beyond the interaction among protein receptors, as lectins, and carbohydrates and can be involved also for enzymes bearing a single active site. This critical overview aims to illustrate and discuss both cases of glycosidases prone to accept inhibitors with a multivalent presentation of the bioactive molecule as well as enzymes displaying a controversial behavior.