Summary

I am a Senior Research Fellow for Protein Engineering in the recently established Centre for Enzyme Innovation (CEI) at the University of Portsmouth. Our focus at the Centre is to develop biochemical, enzymatic solutions to solve some of the major environmental challenges of our time with a particular emphasis on plastics and polymer degradation and recycling.

My expertise is in protein biophysical chemistry with a focus on protein design. I use a variety of techniques borrowed from biophysics, and chemical and molecular biology to develop proteins with new or improved function, and to clarify the natural engineering principles underlying their activity. This approach underlies a substantial part of the Protein Engineering of the CEI. With a focus of learning-by-construction -- using both rational and directed evolution techniques -- we are extending the natural activities of environmentally sourced proteins towards prevalent man-made polymer (plastic) pollutants. Through this engineering, we hope to reveal fundamental biochemical concepts that will help us to identify and build better enzymes for the recycling of other recalcitrant plastics.

This work is embedded in the CEI and the University of Portsmouth, with strong in-house collaborations with Professor John McGeehan (structural biology), Professor Andy Pickford (biophysics), and Dr. Sam Robson (bioinformatics).

In addition, I collaborate with researchers across institutions in the UK and Europe on projects focusing on design of man-made oxidoreductases and new protein-based tools for biomolecular medicine. These projects are built at the interface between protein chemistry and design, leveraging the benefits of both research disciplines.

Biography

I graduated with a BA in Biochemistry (Highest Honors, Phi Beta Kappa) from Swarthmore College, USA, in 2002. I subsequently joined the group of Professor P. Les Dutton, FRS, at the University of Pennsylvania for my graduate research on the chemistry of non-natural, organic, redox cofactors in manually designed proteins, and completed my PhD in Biochemistry and Macromolecular Biophysics in 2010.  My research career continued in Les’s group until I moved to the Chemical Biology Department at the University of Oxford to join Professor Ben G. Davis’s group in 2012, to study protein chemistry. After a year in Oxford, I joined Professor Birte Höcker’s Protein Design Group at the Max Planck Institute for Developmental Biology in Tübingen, Germany. There I initiated several projects with a focus on new protein-based tools for macromolecular delivery into eukaryotic cells, and the creation of new cofactor-binding chimeric proteins. The group moved to the University of Bayreuth, Germany, in 2016, and I completed my postdoctoral training there before joining the CEI in the fall of 2019 as a Senior Research Fellow.

Research interests

My foundational research interest is in understanding the physical and biochemical requirements needed for the creation of proteins with new functions.

My ongoing projects include:

  • Designing and directed evolution of new plastic degrading enzymes
  • Engineering of protein-based transporters for targeted, cellular delivery of macromolecular cargo
  • Development of substrates for characterization of surface modifying enzymes
  • Design of man-made oxidoreductases with tailored electrochemical function
  • Creation of non-natural cofactors for chemical extension of designed proteins

Research outputs

2024

Understanding the catalytic efficiency of two polyester degrading enzymes: an experimental and theoretical investigation

Clark, M., Cox, P. A., König, G., Lichtenstein, B. R., Pickford, A. R., Tornesakis, K., Zahn, M.

5 Nov 2024, In: ACS Omega. 9, 44, p. 44724-44733, 10p.

Investigating the effect of fusion partners on the enzymatic activity and thermodynamic stability of poly(ethylene terephthalate) degrading enzymes

Bemmer, V. L., Cahill, A., Green, K. R., Lichtenstein, B., Oliveira Pessoa, L., Wuscher, L.

17 May 2024, In: Faraday Discussions

2023

Concentration-dependent inhibition of mesophilic PETases on poly(ethylene terephthalate) can be eliminated by enzyme engineering

Allen, M. D., Austin, H. P., Avilan, L., Beckham, G. T., Bemmer, V. L., Clark, M. A., Dominick, G., Graham, R., Johnson, C. W., Koenig, G., Lichtenstein, B., McGeehan, J., Oliveira Pessoa, L., Pickford, A., Zahn, M.

21 Apr 2023, In: ChemSusChem. 16, 8, 12p., e202202277

View all my research outputs