Protease profiling using a fluorescent domino peptide cocktail.

Area of Science:

• Biochemistry
• Proteomics
• Analytical Chemistry

Background:

• Proteases are crucial enzymes involved in numerous biological processes.
• Accurate identification and functional profiling of proteases are essential for understanding disease mechanisms and developing therapeutics.
• Existing methods for protease analysis can be complex and may lack specificity.

Purpose of the Study:

• To develop a versatile and sensitive reagent for protease identification and functional profiling.
• To create a peptide-based tool that generates unique "fingerprints" for different proteases.
• To establish a method for selective detection of N-terminal cleavage products.

Main Methods:

• Synthesis of five hexapeptides containing all 25 possible dipeptides from five amino acid classes (aromatic, hydrophobic, positively charged, negatively charged, small and polar).
• N-terminal fluorescence labeling of peptides with a (7-coumaryl)oxyacetyl group for selective detection.
• Analysis of the peptide cocktail using High-Performance Liquid Chromatography (HPLC) with various proteases.

Main Results:

• The peptide cocktail generated distinct cleavage patterns, or "fingerprints," specific to different proteases.
• Fluorescence labeling enabled selective detection of N-terminal cleavage products, enhancing sensitivity.
• The method demonstrated effectiveness in differentiating and characterizing a variety of proteases.

Conclusions:

• The developed domino peptide cocktail serves as a general and effective reagent for protease identification.
• This approach provides a powerful tool for protease functional profiling.
• The method offers a sensitive and specific means for analyzing protease activity in complex biological samples.