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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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Dataset's files

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			Action	DRS
	HSA_active.fasta	Fasta
	HSA_elastase-trypsin_crosslinks.csv	Csv
	HSA_elastase-trypsin_rep1.apl	Other
	HSA_elastase-trypsin_rep1.raw	Raw
	HSA_elastase-trypsin_rep2.apl	Other

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