Proteomics of Vibrio cholerae.

Area of Science:

• Proteomics
• Biochemistry
• Analytical Chemistry

Background:

• High-throughput mass spectrometry coupled with isobaric tags for relative and absolute quantification (iTRAQ) enables protein identification and quantification across multiple samples.
• Enrichment of specific proteome fractions, such as secreted or membrane proteins, is crucial for detecting low-abundance proteins.
• Existing workflows may not be optimized for the isolation and enrichment of these specific protein classes for subsequent mass spectrometry analysis.

Purpose of the Study:

• To describe a novel workflow for the isolation and enrichment of secreted and membrane proteins.
• To ensure compatibility of the workflow with high-throughput mass spectrometry.
• To improve the detection and quantification of low-abundance proteins.

Main Methods:

• Protein isolation and enrichment targeting secreted and membrane protein fractions.
• Protein reduction, alkylation, and trypsin digestion.
• Peptide labeling using isobaric tags for relative and absolute quantification (iTRAQ) reagent.
• Peptide separation via strong cation exchange chromatography to reduce complexity.
• Final peptide separation by reverse-phase chromatography for MALDI TOF-TOF analysis.

Main Results:

• Successful isolation and enrichment of secreted and membrane proteins.
• Demonstrated compatibility of the workflow with mass spectrometry.
• Enhanced identification and relative quantification of proteins, including low-abundance ones.

Conclusions:

• The described workflow effectively enriches secreted and membrane proteins for mass spectrometry.
• This method improves the detection of low-abundance proteins, advancing proteomic studies.
• The workflow offers a valuable tool for comprehensive proteome analysis.