Engineering Enzymes for Organic Synthesis

Engineering Enzymes for Organic Synthesis

Professor Gideon Grogan, Department of Chemistry, University of York.

Background

Our research group is interested in the identification and characterisation of enzymes and their application to organic synthesis. Biocatalytic processes offer many advantages over conventional catalysis as they are often superior in terms of selectivity, but also because they can operate under mild reaction conditions, and can replace toxic or hazardous reagents in a number of difficult chemical reactions. As a consequence, many industrial processes for the formation of pharmaceutical and agrochemical intermediates now employ enzymes as part of manufacturing routes. However, the performance of natural enzymes is inherently constrained, as they have often evolved to transform perhaps only one substrate type, and only under certain conditions. These limitations can now be challenged very effectively using methods of enzyme engineering that have been developed in recent years.

Experimental Approach

In our group, new and interesting enzymes are identified and then characterized using a range of biochemical techniques, including X-ray crystallography. Synthetic organic chemistry is used to prepare enzyme substrates and product standards. Once we have obtained the structure of an enzyme, we are in a good position to engineer the active site for improved or altered characteristics, including expanded substrate specificity, but maybe also increased thermostability or improved performance in the presence of organic solvents. We can also engineer enzymes using more random approaches, such as directed evolution. Many kinds of enzymes have been investigated by the group and our current interests include: Oxidoreductases (Amine Dehydrogenases, Imine Reductases and Reductive Aminases) for the preparation of chiral amines; Oxygenases (Unspecific Peroxygenases and P450s), for the selective hydroxylation of carbon atoms; and Ligases (Amide Bond Synthetases) for the preparation of amides, one of the most important functional groups encountered in pharmaceutical synthesis.

While our enzyme targets change from year to year, and new projects are constantly introduced, you would, as part of any PhD study use techniques such as organic chemistry, PCR, gene expression and protein/enzyme analysis, protein crystallization and protein structure building and refinement, to characterise new enzyme transformations and obtain new structures. You will then use contemporary techniques in enzyme engineering to design and test improved enzymes for process performance. Our projects are frequently performed in collaboration with industrial partners, so there is always excellent scope for interactions outside the laboratory.

Training

All research students follow the innovative Doctoral Training in Chemistry (iDTC) at York, a cohort-based training programme that supports the development of both scientific and transferable skills. All research students take the Core training package, which provides a grounding in the skills required for their research, and also transferable skills to enhance employability opportunities following graduation. Core training is progressive and takes place at appropriate points throughout a student's higher degree programme, with the majority of training taking place in Year 1. In conjunction with the Core training, students, in consultation with their supervisor(s), select training related to the area of their research.

Students appointed to our projects will be supervised primarily in the York Structural Biology Laboratory at York, and can be trained in organic synthesis and analysis, gene cloning, construct engineering, heterologous expression, biotransformations, gene mutation and X-ray crystallography. The projects will also provide training in enzyme purification and enzyme assays using HPLC/MS, GC/MS and plate-based assays. Students will also benefit from compulsory programmes of postgraduate study and skills training offered through the Departments of Chemistry and Biology at York, including literature skills, and frequent written and oral presentations.

All Chemistry research students have access to our innovative Doctoral Training in Chemistry (iDTC): cohort-based training to support the development of scientific, transferable and employability skills: https://www.york.ac.uk/chemistry/postgraduate/cdts/ 

The Department of Chemistry holds an Athena SWAN Gold Award and is committed to supporting equality and diversity for all staff and students. The Department strives to provide a working environment which allows all staff and students to contribute fully, to flourish, and to excel: https://www.york.ac.uk/chemistry/ed/ .