A straightforward gel-free proteomics pipeline assisted by liquid isoelectric focusing (OFFGEL) and mass spectrometry analysis to study bovine meat proteome

Bovine sarcoplasmic sub-proteome was studied through a straightforward gel-free pipeline supported by liquid isoelectric focusing (OFFGEL) protein fractionation coupled to liquid chromatography-mass spectrometry (LC-MS) analysis. Full-MS and data-dependent MS/MS analyses were simultaneously performed by a conventional three-dimensional ion-trap addressing targeted quantitative and untargeted qualitative research, respectively. There were unambiguously identified 47 proteins distributed along 12 OFFGEL fractions assayed. Regarding intermediate- and high-abundant peptides, bulky quantitative data processing performed by MZmine 2 freeware yielded a satisfactory linearity and coefficient of variation with r(2)in the 0.95-0.99 range and about 25%, respectively. Up to 41 peptides from 20 identified proteins were relatively quantified throughout OFFGEL fractions. This reliable, flexible and affordable gel-free proteomic approach could be readily implemented by industry to improve quality assessment of protein-based food products.

Automated summary

The study of bovine sarcoplasmic sub-proteome was conducted using liquid isoelectric focusing (OFFGEL) protein fractionation combined with liquid chromatography-mass spectrometry (LC-MS) analysis. A total of 47 proteins were identified across 12 OFFGEL fractions, showcasing the reliability and effectiveness of the approach. The method, which involved quantitative and qualitative analyses, demonstrated its potential for improving quality assessment of protein-based food products in the industry.