Synthetic Knockout Protein Standard for Evaluating Interference in Tandem Mass Tag-Based Proteomics

Area of Science:

• Proteomics
• Analytical Chemistry
• Biochemistry

Background:

• Isobaric labeling offers advantages for unbiased, proteome-wide studies, including reduced missing values and enhanced quantitative precision.
• Ion interference, caused by coelution and coanalysis of peptides, can distort quantitative ratios in tandem mass tags (TMT)-based proteomics.

Purpose of the Study:

• To introduce a synthetic KnockOut standard (sKO) for assessing ion interference in TMT-based proteomics.
• To demonstrate the utility of the sKO standard in evaluating interference across varying peptide concentrations and mass spectrometry acquisition strategies.

Main Methods:

• Development of a synthetic KnockOut standard (sKO) using TMTpro-labeled peptides from nonhuman proteins mixed with a human proteome background.
• Application of the sKO standard to investigate ion interference under different peptide abundance levels (up to 30-fold change).
• Evaluation of interference using diverse mass spectrometer data acquisition strategies.

Main Results:

• The sKO standard effectively revealed ion interference effects at various peptide concentrations.
• The sKO standard provided insights into optimizing mass spectrometry acquisition strategies for improved data quality.
• Demonstrated the potential of sKO for enhancing high-throughput proteomics workflows.

Conclusions:

• The synthetic KnockOut standard is a valuable tool for quantifying and mitigating ion interference in TMT proteomics.
• sKO facilitates the rational design of acquisition strategies to improve proteomic data accuracy and reliability.
• This approach supports the development of more robust and efficient high-throughput proteomics workflows.