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11:44
Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
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Characterization of cyclic peptides containing disulfide bonds
Mindy Johnson1, Mingtao Liu1, Elaine Struble1
1Pharmaceutical Development Section, Biosciences Division, SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025 United States of America.
Journal of Pharmaceutical and Biomedical Analysis
|March 18, 2015
Summary
Analyzing cyclic peptides with disulfide bonds requires advanced techniques. This study highlights the power of 2D NMR and ESI MS for peptide structure elucidation and introduces an improved RP-HPLC method.
Area of Science:
- Biochemistry
- Analytical Chemistry
- Organic Chemistry
Background:
- Structural analysis of cyclic peptides, particularly those with disulfide bonds, presents significant challenges compared to linear peptides.
- Indirect analytical methods are often necessary for rigorous structural proof of these complex molecules.
Purpose of the Study:
- To characterize three cyclic peptides: p-Cl-Phe-DPDPE, DPDPE, and CTOP.
- To demonstrate the utility of advanced analytical techniques for peptide structure determination.
- To present a novel and improved method for trifluoroacetic acid analysis.
Main Methods:
- Two-dimensional Nuclear Magnetic Resonance (2D NMR) spectroscopy.
- Electrospray Ionization tandem Mass Spectrometry (ESI MS/MS).
- Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC) for trifluoroacetic acid analysis.
Main Results:
- Successful characterization of the cyclic peptides p-Cl-Phe-DPDPE, DPDPE, and CTOP using 2D NMR and ESI MS/MS.
- Demonstration of the high potential of these combined techniques for complex cyclic peptide analysis.
- Development of a new RP-HPLC method for trifluoroacetic acid analysis that is robust, simple, and efficient.
Conclusions:
- 2D NMR and ESI MS/MS are powerful tools for the structural elucidation of cyclic peptides with disulfide bonds.
- The newly developed RP-HPLC method offers a significant improvement for trifluoroacetic acid analysis in peptide research.
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