Research

Mechanistic Studies of Enzymatic and Non-enzymatic Glycosides Hydrolyses

In humans and other living systems, the addition and removal of sugar molecules to or from functional biomolecules is tightly regulated. Some of the energy that we get from our diet is used to ensure that molecules within the body have the correct sugars attached to them, and then once those molecules are no longer needed, the components – such as the sugars – are recycled to minimize the waste of valuable resources. If any of these processing systems go awry, it can lead to serious consequences for the organism’s health. The aim of this study is to employ advanced techniques such as nuclear magnetic resonance (NMR) to investigate how these important sugars are degraded by enzymes or through uncatalyzed mechanisms. This critical information can then guide the development of inhibitors that can serve as drug molecules or mechanistic probes.

Design and Synthesis of Transition State Analogue Inhibitors

An ongoing challenge for the development of therapeutic agents that can be used for treating disease that are associated with bacterial or viral glycoside hydrolases is to design highly selective inhibitors. An ideal inhibitor would precisely mimic the enzyme-catalyzed transition state. Thus, we use our knowledge of transition state structures to design, and then make, stable compounds in which the overall shape and charge are as close as possible to the critical transitions state.

Development of Mechanism-based Covalent Inhibitors

A second approach our lab employs to decrease the enzymatic activity of glycosidases is through the development and application of covalent inhibitors. This class of molecules are distinct from most inhibitors because they do not permanently disable the target enzyme. In contrast, most other inhibitors that covalently bond to an enzyme essentially ‘kill’ it by blocking enzyme reactivation forevermore. Using mechanism-based covalent inhibitor, it is possible to examine cellular responses in more detail; for example, the inhibitor could allow us to observe the effect of a potential drug in a diseased cell by monitoring the cellular response as the activity of a critical carbohydrate processing enzyme decreases and then subsequently returns to baseline levels.