A Recombinant Approach For Stapled Peptide Discovery YieldsInhibitors of the RAD51 Recombinase

Pantelejevs, T.; Zuazua-Villar, P.; Koczy, O.; Counsell, A. J.; Walsh, S. J.; Robertson, N. S.; Spring, D. R.; Downs, J. A.; Hyvonen, M.

doi:10.1101/2023.02.24.529929

bioRxiv · 10.1101/2023.02.24.529929

A Recombinant Approach For Stapled Peptide Discovery YieldsInhibitors of the RAD51 Recombinase

Pantelejevs, T.·Zuazua-Villar, P.·Koczy, O.·Counsell, A. J.·Walsh, S. J.·Robertson, N. S.·Spring, D. R.·Downs, J. A.·Hyvonen, M.

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Abstract

Stapling is a macrocyclisation method that connects amino acid side chains of a peptide to improve its pharmacological properties. We describe an approach for stapled peptide preparation and biochemical evaluation that combines recombinant expression of fusion constructs of target peptides and cysteine-reactive divinyl-heteroaryl chemistry, as an alternative to solid-phase synthesis. We then employ this workflow to prepare and evaluate BRC-repeat-derived inhibitors of the RAD51 recombinase, showing that a diverse range of secondary structure elements in the BRC repeat can be stapled without compromising binding and function. Using X-ray crystallography, we elucidate the atomic-level features of the staple moieties. We then demonstrate that BRC-repeat-derived stapled peptides can disrupt RAD51 function in cells following ionising radiation treatment.

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Pantelejevs, T., Zuazua-Villar, P., Koczy, O., Counsell, A. J., Walsh, S. J., Robertson, N. S., Spring, D. R., Downs, J. A., Hyvonen, M.. 2023-02-24. A Recombinant Approach For Stapled Peptide Discovery YieldsInhibitors of the RAD51 Recombinase. https://doi.org/10.1101/2023.02.24.529929

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