Phd on topic: Active site redesign of ene reductases


Research interest and scientific background: The Gruber group is interested in structure-function relationships of enzymes, focusing on experimental structure determination, structural bioinformatics and molecular modeling. These studies involve enzymes ranging from flavoenzyme and B12-dependent enzymes to proteases and lipases and aim at a deeper understanding of enzymatic mechanisms of enzymes in general as well as at engineering and (re)designing of biocatalysts for specific applications.

Affiliation: The student will work at the Institute of Molecular Biosciences at the University of Graz. This project is directly connected to the doc.funds CataLOX.

Hypothesis and objective: Flavin-dependent ene reductases from the Old-Yellow-Enzyme (OYE) catalyze the stereospecific reduction of activated C=C double bonds. They have recently also been shown to facilitate the reductive formation of C-C bonds yielding carbocyclic compounds, albeit with quite narrow substrate specificity. In collaboration with Rolf Breinbauer and Peter Macheroux, the project aims at using in silico modelling and (structural) bioinformatics methods to identify suitable candidates from the OYE-family (or structurally related enzymes) and to (re)design the active sites of those enzymes to widen the substrate acceptance and to allow the synthesis of larger carbocyclic structures.

Experimental approaches: The student will use a wide range of (structural) bioinformatics and molecular modeling techniques to identify suitable candidate enzymes and engineer and (re)design the respective active sites. X-ray crystal structures will be determined of the most promising candidates preferably in complex with substrates or products as part of a feedback process for further engineering of the designed biocatalysts.

The student will strongly interact with other research groups of the doc.funds Molecular Metabolism, the doc.funds CataLOX and the Austrian Centre of Industrial Biotechnology (acib).

References:

  1. K. Heckenbichler, A. Schweiger, L. A. Brandner, A. Binter, M. Toplak, P. Macheroux, K. Gruber, R. Breinbauer, Asymmetric reductive carbocyclization using engineered ene reductases, Angew. Chem. Int. Ed., 57 (2018), 7240-7244.