Crosslinking dipeptide rapid identification method

Abstract

The present invention provides a method for rapid identification of cross-linked dipeptides, comprising: 1) extracting effective spectral peaks in the tandem spectrogram to be identified, and searching for the fragment index to obtain the corresponding peptide sequence as a candidate α according to the mass corresponding to each effective spectral peak Peptide sequence, wherein the fragment index records the mass of each fragment and its corresponding peptide sequence; 2) For each candidate α-peptide sequence, calculate the corresponding β-peptide mass according to the precursor ion mass of the tandem spectrum to be identified, Then obtain the corresponding candidate β-peptide sequence, combine the candidate α-peptide sequence and the corresponding candidate β-peptide sequence to obtain a candidate cross-linked dipeptide; 3) finely match the candidate cross-linked dipeptide obtained in step 2) with the tandem spectrum, Get the identification result. The invention does not need to use a special cross-linking agent; the search speed is fast, the identification efficiency is high; and the 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...

AI Technical Summary

Problems solved by technology

However, in this method, nearly half of the peptides in the sequence library have to be roughly scored with each spectrum, which has the problem of a large amount of calculation, which leads to low identification efficiency

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