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A recombinant approach for stapled peptide discovery yields inhibitors of the RAD51 recombinase.

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.

SUBMITTER: Pantelejevs T

PROVIDER: S-EPMC10699557 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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A recombinant approach for stapled peptide discovery yields inhibitors of the RAD51 recombinase.

Pantelejevs Teodors T Zuazua-Villar Pedro P Koczy Oliwia O Counsell Andrew J AJ Walsh Stephen J SJ Robertson Naomi S NS Spring David R DR Downs Jessica A JA Hyvönen Marko M

Chemical science 20231121 47

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, showi ...[more]

PMID: 38075664

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