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Sequential digestion with Trypsin and Elastase in cross-linking/mass spectrometry

ABSTRACT: Cross-linking/mass spectrometry has become an important approach for studying protein structures and protein-protein interactions. The amino acid composition of some protein regions impedes the detection of cross-linked residues, although it would yield invaluable information for protein modelling. Here, we report on a sequential digestion strategy with trypsin and elastase to penetrate regions with a low density of trypsin cleavage sites. We exploited intrinsic substrate recognition proper-ties of elastase to specifically target larger tryptic peptides. Our application of this protocol to the TAF4-12 complex allowed us to identify cross-links in previously inaccessible regions.

INSTRUMENT(S): Orbitrap Fusion Lumos, LTQ Orbitrap Elite

ORGANISM(S): Homo Sapiens (human) Schizosaccharomyces Pombe

SUBMITTER: Therese Dau

LAB HEAD: Juri Rappsilber

PROVIDER: PXD011459 | Pride | 2019-03-07

REPOSITORIES: Pride

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Proteomics Using Proteases Alternative to Trypsin Benefits from Sequential Digestion with Trypsin

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2021-06-07 | PXD017321 | Pride

β-TrCP and Casein Kinase II mediated degradation of cyclin F controls timely mitotic progression

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A truncated MRE11 form induced by SPRTN is deficient in DNA repair and radiosensitises cancer cells

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Sequence and structural Sequence and structural variations determining the recruitment of WNK kinases to the KLHL3 E3 ligase

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Improved analysis of crosslinking mass spectrometry data with Kojak 2.0, advanced by integration into the Trans-Proteomic Pipeline

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2017-03-09 | PXD004749 | Pride

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