Name: Data for 'Light-Driven, Posttranslation Installation of Reactive Protein Side Chains'

Description: C–C side chain alteration within intact proteins has the potential to allow native, chemical, post-translational modification mutagenesis (‘protein editing’) of sequences. Whilst 2e- heterolytic methods (via C-/C+) are highly limited in biological environments and molecules, radical (C•) methods have shown early promise due to apparently well-matched selectivities. However, current methods, reagents, and conditions for C• generation are either limited in site-selectivity and/or only partially compatible with proteins. Here we describe the mildest methods to date by exploiting visible light-driven, electron-transfer catalysts benignly matched to easily accessible, side-chain precursors that can form C–C bonds to the highly active SOMO-phile dehydroalanine in water. Control of the reaction redox environment by simple alteration of catalyst + additives + light promotes initiation under low oxidation conditions allowing site-selective ‘editing’ modification with excellent conversions and without protein damage. In situ generation of easily oxidized boronic acid catechol ester derivatives generates RH2C• radicals that form the native (βCH2-γCH2) linkage of natural residues and PTMs (using as little as 100 equiv.) whereas in situ potentiation of pyridylsulfonyl derivatives by Fe(II) generates RF2C• radicals that form equivalent (βCH2-γCF2) linkages to create residues bearing instead ‘zero-size’ H→F labels (using as little as 1-2 eq in 15 min). These reactions are mild and chemically-tolerant enough to incorporate an unprecedented range of chemical functionality, used here to modify diverse protein scaffolds and sites with >50 unique residues/sidechains. Moreover, initiation can be applied chemoselectively in the presence of sensitive and, even, inherently-reactive groups in C• precursors, enabling the installation of previously incompatible sidechains. This, in turn, provides access to new functional groups and reactivity in proteins, used here to (a) install further, stabilized radical precursors for on-protein radical generation and reaction; (b) study enzyme function with natural, unnatural, and ‘zero-size’-labeled PTM substrates that allowed remote, simultaneous sensing of both stereochemistry and modification state in proteins; and (c) create access to generalized ‘alkylator proteins’ with a spectrum of activity – reacting diversely with small molecules at one extreme or that instead require good mimicry and partner proximity to covalently and selectively crosslink specific protein targets (thereby selectively capturing even transient protein-protein interaction) at the other. In this way, we suggest that the exploitation of new reactions and chemical groups on proteins (such as stabilized radicals or size-matched reactive alkylators and ‘zero-size’ labels) could prove to be useful tools in revealing function.

DOI: 10.5287/bodleian:9ewjq268q

Location: https://ora.ox.ac.uk/objects/uuid:2a618e7e-551b-4360-a2de-237453d49a31

Resository: https://ora.ox.ac.uk

Start date: 2020-09-23 00:00:00 UTC

End date:

Related Article: Light-driven post-translational installation of reactive protein side chains

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