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Multiple Proteases to Localize Oxidation Sites

ABSTRACT: Proteins present in cellular environments with high levels of reactive oxygen and nitrogen species and/or low levels of antioxidants are highly susceptible to oxidative post-translational modification (PTM). Irreversible oxidative PTMs can generate a complex distribution of modified protein molecules, recently termed as proteoforms. Using ubiquitin as a model system, we mapped oxidative modification sites using trypsin, Lys-C, and Glu-C peptides. Several M+16 Da proteoforms were detected as well as proteoforms that include other previously unidentified oxidative modifications. This work highlights the use of multiple protease digestions to give insights to the complexity of oxidative modifications possible in bottom-up analyses.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Bos Taurus (bovine)

SUBMITTER: Liqing Gu

LAB HEAD: Rena A. S. Robinson

PROVIDER: PXD001204 | Pride | 2016-07-06

REPOSITORIES: Pride

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Dataset's files

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			Action	DRS
	ESI_OX_UBI_Full.raw	Raw
	ESI_UM_UBI_Full.raw	Raw
	GluC.msf-pride.xml-merged.pride.mgf.gz	Mgf
	GluC.msf-pride.xml-merged.pride.mztab.gz	Mztab
	GluC.msf-pride.xml-merged.xml.gz	Xml

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Publications

Multiple proteases to localize oxidation sites.

Gu Liqing L Robinson Renã A S RA

PloS one 20150316 3

Proteins present in cellular environments with high levels of reactive oxygen and nitrogen species and/or low levels of antioxidants are highly susceptible to oxidative post-translational modification (PTM). Irreversible oxidative PTMs can generate a complex distribution of modified protein molecules, recently termed as proteoforms. Using ubiquitin as a model system, we mapped oxidative modification sites using trypsin, Lys-C, and Glu-C peptides. Several M+16 Da proteoforms were detected as well ...[more]

PMID: 25775238

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