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bioRxiv · 10.1101/450981

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

Dau, T.·Gupta, K.·Berger, I.·Rappsilber, J.
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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 properties 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.

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Dau, T., Gupta, K., Berger, I., Rappsilber, J.. 2018-10-23. Sequential digestion with Trypsin and Elastase in cross-linking/mass spectrometry. https://doi.org/10.1101/450981

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