Phd on topic: Fitness landscapes of oxidoreductases


Research interest and scientific background: The Kourist group is interested in structure-function relationships of enzymes, with focus on enzymatic decarboxylation and oxyfunctionalization. While directed enzyme evolution has led to an impressive number of improved biocatalysts, it is often difficult to use the results for an increase of the mechanistic knowledge. This is particularly true for amino acid exchanges in peripheral positions, where an influence on the mechanism is often not obvious.

Affiliation: The student will work at the Institute of Molecular Biotechnology at the Graz University of Technology under the supervision of Robert Kourist. This project is directly connected to the doc.fund CataLOX.

Hypothesis and objective: The project aims to gain comprehensive understanding of structure-function relationships of oxidoreductases. Focus lies on the investigation of the particular role of peripheral amino acid substitutions on protein dynamics and specific properties such as entrance tunnels for water and co-substrates.

Experimental approaches: The student will follow a combinatorial approach for the diversification of genes. Aim is to correlate the catalytic properties of a large number of variants with amino acid substitutions. The student will perform all steps from the design of a library to high-throughput screening and enzymological studies on variants with altered properties.

The student will strongly interact with other research groups of the doc.funds Molecular Metabolism, the doc.funds CATALOX, the Austrian Centre of Industrial Biotechnology (acib) and the research and training network NAWI Graz and BioTechMed Graz.

References:

  1. F. Busch, N. Hülsemann, J. Enoki, K. Miyamoto, M. Bocola, R. Kourist, Semiempirical QM/MM calculations reveal a step-wise proton transfer and an unusual thiolate pocket in the mechanism of the racemizing mutant G74C of arylmalonate decarboxylase, Cat. Sci. Technol., 6 (2016) 4937 - 4944.
  2. S.K. Gaßmeyer, J. Wetzig, C. Mügge, M. Assmann, J. Enoki, L. Hilterhaus, R. Zuhse, K. Miyamoto, A. Liese, R. Kourist, Arylmalonate Decarboxylase‐Catalyzed Asymmetric Synthesis of Both Enantiomers of Optically Pure Flurbiprofen, ChemCatChem, 8 (2016) 916-921.
  3. Á. Gómez-Baraibar, D. Reichert, C. Mügge, S. Seger, H. Gröger, R. Kourist, A sequential one-pot cascade reaction combining an encapsulated decarboxylase with metathesis for the synthesis of bio-based antioxidants, Angew. Chem., Int. Ed., 55 (2016) 14823–14827.