Grant: Discovery Grants Program - Individual

Enzymes are becoming increasingly important products for several industries. They are safe for the environment, cheaper than ever, and, when used under optimal conditions, much more efficient than chemical catalysts. With recent advances in protein engineering and directed evolution, customized enzymes will become available for industrial processes for which the native enzymes were unsuitable. At the heart of enzyme efficacy as industrial biocatalysts are stability issues. Indeed, enzymes have to stand rather harsh conditions in order to provide economical alternatives to polluting chemicals; customizing enzymes for industrial application will therefore require an in-depth understanding of stability determinants in proteins. In continuity with our ongoing research programme, we intend to shed light on the structural features that determine enzyme behavior, particularly enzyme stability. To this end, we will use a hydrolase (endopolygalacturonase) as a model enzyme because of its simplicity and because of its multiple potential applications in various industries. By a judicious choice of mutations or by random mutagenesis, we will attempt to modulate the response of this enzyme to pH, temperature and other destabilizing conditions. Spectroscopic and enzymatic methods will be used to characterize the impact of amino acid replacement on selected properties. By comparing enzyme properties before and after modification, we will provide a level of understanding that will then be useful in designing strategies for optimizing enzyme as industrial biocatalysts.