Working Paper
Authors
- Bradley Doak Monash University ,
- Rebecca Whitehouse Monash University ,
- Kieran Rimmer Monash University ,
- Martin Williams Monash University ,
- Begona Heras La Trobe University ,
- Sofia Caria Monash University ,
- Olga Ilyichova Monash University ,
- Mansha Vazirani Monash University ,
- Biswaranjan Mohanty Monash University & University of Sydney ,
- Jason Harper UNSW Sydney ,
- Martin Scanlon
Monash University ,
- Jamie Simpson Monash University
Abstract
Disulfide bond protein A (DsbA) is an oxidoreductase enzyme that catalyzes the formation of disulfide bonds in Gram-negative bacteria. In Escherichia coli, DsbA (EcDsbA) is essential for bacterial virulence, thus inhibitors have the potential to act as antivirulence agents. A fragment-based screen was conducted against EcDsbA and herein we describe the development of a series of compounds based on a phenylthiophene hit identified from the screen. A novel thiol reactive and “clickable” ethynylfluoromethylketone was designed for reaction with azide-functionalized fragments to enable rapid and versatile attachment to a range of fragments. The resulting fluoromethylketone conjugates showed selectivity for reaction with the active site thiol of EcDsbA, however unexpectedly, turnover of the covalent adduct was observed. A mechanism for this turnover was investigated and proposed which may have wider ramifications for covalent reactions with dithiol-disulfide oxidoreducatases.
Content

Supplementary material

Fluoromethylketone-fragment conjugates designed as covalent modifiers of EcDsbA are atypical substrates
Methods, characterisation and supporting information