A rapid identification method for cross-linked dipeptides

Abstract

The invention provides a crosslinking dipeptide rapid identification method, comprising: 1) extracting effective spectrum peaks in a to-be-identified series-connected spectrogram, according to mass corresponding to each effective spectrum peak, searching a fragment index, to obtain a corresponding peptide fragment sequence as a candidate [alpha] peptide sequence, wherein the fragment index records mass of each fragment and the peptide fragment sequence corresponding to the mass of each fragment; 2) for each candidate [alpha] peptide sequence, according to parent ion mass of the to-be-identified series-connected spectrogram, calculating corresponding [beta] peptide mass, to obtain a corresponding candidate [beta] peptide sequence, combining the candidate [alpha] peptide sequence with the corresponding candidate [beta] peptide sequence, to obtain candidate crosslinking dipeptide; 3) matching the candidate crosslinking dipeptide obtained in the step 2) with the series-connected spectrogram in a fine manner, to obtain an identification result. The method does not need to use a special cross-linking agent, searching speed is fast, identification efficiency is high, and search sensitivity is high.

Description

technical field

[0001] The invention relates to the technical field of bioinformatics, in particular, the invention relates to a rapid identification method for cross-linked dipeptides. Background technique

[0002] Chemical cross-linking combined with mass spectrometry (referred to as cross-linking mass spectrometry) is an effective method for large-scale research on protein-protein interactions and protein folding. The core research and identification object is cross-linked dipeptide, which originates from the Synlocation points provide information that sequences are far apart but spatially close together. In cross-linked mass spectrometry, the identification of cross-linked dipeptides is mainly achieved by database search technology of tandem spectra. However, unlike the traditional single-peptide sequence search, the candidate space of cross-linked dipeptide database search grows to the square of the original single-peptide sequence, which brings challenges to large-sca...

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