Robust phosphoproteome enrichment using monodisperse microsphere-based immobilized titanium (IV) ion affinity...

Area of Science:

• Proteomics
• Biochemistry
• Analytical Chemistry

Background:

• Mass spectrometry (MS)-based proteomics is crucial for analyzing protein phosphorylation.
• Efficient phosphopeptide enrichment is essential due to phosphorylation's substoichiometric nature and cellular complexity.
• Novel materials offer improved phosphopeptide enrichment.

Purpose of the Study:

• To present a detailed protocol for preparing and using monodisperse microsphere-based titanium(IV) immobilized metal ion affinity chromatography (Ti(4+)-IMAC) adsorbents.
• To discuss critical steps and potential pitfalls in phosphoproteomics sample preparation, enrichment, and mass spectrometric analysis.
• To demonstrate the protocol's applicability for both single-protein and whole-proteome phosphoproteomics.

Main Methods:

• Preparation of monodisperse microsphere-based Ti(4+)-IMAC adsorbents.
• Enrichment of phosphopeptides using the prepared Ti(4+)-IMAC material.
• Mass spectrometric analysis and bioinformatics analysis for site localization.

Main Results:

• The developed Ti(4+)-IMAC material provides robust and efficient phosphopeptide enrichment.
• The protocol addresses key aspects from sample lysis to MS data analysis and site localization.
• The method is validated for both targeted and global phosphoproteomics studies.

Conclusions:

• The presented protocol offers a reliable method for phosphopeptide enrichment using Ti(4+)-IMAC.
• This approach facilitates comprehensive phosphoproteomics analysis.
• The protocol is suitable for diverse applications in phosphoproteomics research.