Chemical determination of polypeptide hormones

Area of Science:

• Biochemistry
• Analytical Chemistry
• Endocrinology

Background:

• Peptide hormones play crucial roles in physiological processes.
• Accurate detection and quantification of peptide hormones are essential for research and diagnostics.
• Existing methods for peptide hormone analysis can be complex and time-consuming.

Purpose of the Study:

• To develop and validate a novel analytical method for detecting and quantifying peptide hormones in tissue extracts.
• To demonstrate the utility of the method by identifying specific peptide hormones in porcine intestinal extracts.
• To explore the potential of this methodology for isolating known and unknown polypeptides.

Main Methods:

• Enzymatic release of COOH-terminal polypeptide fragments containing alpha-amide groups.
• Conversion of released fragments into fluorescent dansyl derivatives.
• Identification of dansyl derivatives using thin-layer chromatography.

Main Results:

• Successfully demonstrated the presence of secretin, cholecystokinin, and vasoactive intestinal peptide in porcine intestinal extracts.
• Identified specific COOH-terminal amide fragments: valine (or leucylvaline) amide, phenylalanine amide, and asparagine (or leucylasparagine) amide.
• The method allows for approximate quantitation of peptide hormones.

Conclusions:

• The developed analytical methodology provides a sensitive and reliable approach for peptide hormone detection.
• This method can be adapted for the isolation of known and previously uncharacterized polypeptides.
• The technique offers a valuable tool for biochemical and endocrinological research.