Label-free protein quantification method based on mass spectrum

Abstract

The invention discloses a label-free protein quantification method based on a mass spectrum. The label-free protein quantification method comprises the following steps: acquiring corresponding theoretical peptide fragment set by theoretical enzyme digestion of a theoretical protein sequence data bank; extracting extracted-ion-flow chromatograms (XIC) of all ions on a primary mass spectrum (MS) and calculating corresponding retention time (RS) and mass-to-charge ratios (M / Z) on the extracted-ion-flow chromatograms; establishing a multi-mapping relation table about isotopic distribution and retention time of the theoretical peptide fragment set and the extracted-ion-flow chromatograms. According to the method, a label-free protein quantification algorithm combined with an intelligent optimization algorithm is adopted, the optimal mapping relation between the theoretical peptide fragment set and the extracted-ion-flow chromatograms is obtained from the multi-mapping relation table by means of the intelligent optimization algorithm, and a quantification result is obtained. By means of efficient qualitative analysis of peptide fragments, higher protein detection coverage can be realized, so that high-throughput quantification of proteins is realized. Research proves that change of expressive abundance of the proteins in cells has great significance in early diagnosis of diseases.

Description

technical field [0001] The invention belongs to the field of bioinformatics, in particular to a standard-free protein quantification method based on mass spectrograms. Background technique [0002] Quantitative proteomic methods have been developed in recent decades and are of great significance for the study of biomarkers and drug targets. Traditional methods such as two-dimensional fluorescence differential gel electrophoresis are rarely used because of their inherent drawbacks: it is difficult to effectively separate and resolve low-abundance and low-hydrophobicity proteins. Mass spectrometry is a high-throughput analytical proteomics method capable of analyzing complex samples through the collection of large amounts of data. According to whether isotope labeling is used, mass spectrometry can be divided into isotope-labeled quantitative method and label-free quantitative method. [0003] The quantitative method of isotope labeling has the disadvantages of complex equip...

AI Technical Summary

Problems solved by technology

Traditional methods such as two-dimensional fluorescence differential gel electrophoresis are rarely used because of their inherent drawbacks: it is difficult to efficiently separate and resolve low-abundance and low-hydrophobicity proteins

[0003] The quantitative method of isotope labeling has the disadvantages of complex equipment, expensive isotope labeling and special requirements for data analysis software.

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