Dataset Information

Stereoretentive Post-Translational Protein Editing

ABSTRACT: Chemical post-translational methods now allow convergent side-chain editing of proteins as a form of direct chemical mutagenesis without needing to resort to genetic intervention. Current approaches that allow the creation of constitutionally native side-chains via C–C formation using off-protein carbon-centred C• radicals added to unnatural amino acid radical acceptor SOMOphile ‘tags’ such as dehydroalanine are benign and wide-ranging. However, they also typically create epimeric mixtures of D-/L-residues. Here we describe a light-mediated desulfurative method that, through the creation and reaction of stereoretained on-protein L-alanyl Cβ• radicals, allows Cβ–Hγ, Cβ–Oγ, Cβ–Seγ, Cβ–Bγ and Cβ–Cγ bond formation to flexibly generate site-selectively edited proteins with full retention of native stereochemistry under mild conditions from a natural amino acid. This methodology shows great potential to explore protein side-chain diversity and construct useful bioconjugates. This dataset contains LCMS data of tryptic digests of a PstS protein selectively modified by different radical acceptors (modification site D178). In total, 16 LCMS files are presented along with the results of the identification by MSFragger, corresponding to the variants of the PstS protein with different modifications.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Escherichia Coli

SUBMITTER: Nikita Levin

LAB HEAD: Benjamin Guy Davis

PROVIDER: PXD036570 | Pride | 2023-05-10

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	LUMOS_NGL_NGL_220803_psts_mod01_CysToAla_10.raw	Raw
	LUMOS_NGL_NGL_220803_psts_mod01_CysToAla_10_c.pepXML	Pepxml
	LUMOS_NGL_NGL_220803_psts_mod01_CysToAla_10_uncalibrated.mgf	Mgf
	LUMOS_NGL_NGL_220803_psts_mod03_SePh_12.raw	Raw
	LUMOS_NGL_NGL_220803_psts_mod03_SePh_12_c.pepXML	Pepxml

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Publications

Stereoretentive Post-Translational Protein Editing.

Fu Xia-Ping XP Yuan Yizhi Y Jha Ajay A Levin Nikita N Giltrap Andrew M AM Ren Jack J Mamalis Dimitrios D Mohammed Shabaz S Davis Benjamin G BG

ACS central science 20230224 3

Chemical post-translational methods allow convergent side-chain editing of proteins without needing to resort to genetic intervention. Current approaches that allow the creation of constitutionally native side chains via C-C bond formation, using off-protein carbon-centered C· radicals added to unnatural amino acid radical acceptor (SOMOphile, singly occupied molecular orbital (SOMO)) "tags" such as dehydroalanine, are benign and wide-ranging. However, they also typically create epimeric mixture ...[more]

PMID: 36968537

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