Hydrophobin-coated plates as matrix-assisted laser desorption/ionization sample support for peptide/protein analysis

Area of Science:

• Biochemistry
• Proteomics
• Materials Science

Background:

• Fungal hydrophobins are amphipathic proteins known for self-assembly and surface modification.
• Vmh2 hydrophobin from Pleurotus ostreatus forms stable layers capable of binding active proteins.
• Matrix-assisted laser desorption/ionization (MALDI) is a key technique in mass spectrometry for analyzing biomolecules.

Purpose of the Study:

• To develop a novel coating for MALDI sample plates using Vmh2 hydrophobin.
• To evaluate the efficacy of Vmh2-coated plates for protein and peptide analysis, including desalting.
• To assess the suitability of this method for complex biological samples and proteomic applications.

Main Methods:

• Preparation of Vmh2 hydrophobin from Pleurotus ostreatus mycelial cultures.
• Coating of steel MALDI sample plates with the self-assembled Vmh2 layer.
• Analysis of standard proteins and tryptic peptides across a wide concentration range (nanomolar-femtomolar).
• Analysis of crude human serum as a complex biological sample.
• Comparison with standard desalting techniques and other on-plate desalting methods.

Main Results:

• Vmh2-coated MALDI plates demonstrated a simple and effective method for desalting.
• Successful analysis of protein and peptide mixtures, including in the presence of salts and denaturants.
• Acquisition of spectra from crude human serum over a wide mass range.
• The Vmh2 coating method showed comparable or superior performance to existing desalting techniques.

Conclusions:

• Vmh2 hydrophobin coating provides a straightforward and efficient desalting solution for MALDI plates.
• This novel approach is highly suitable for developing lab-on-a-plate platforms for proteomic analyses.
• The Vmh2-coated MALDI plate technology has significant potential to advance high-throughput proteomic studies.