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Sample Preparation and Relative Quantitation using Reductive Methylation of Amines for Peptidomics Studies
Published on: November 4, 2021
Analysis of Endogenous D-Amino Acid-Containing Peptides in Metazoa
Lu Bai1, Sarah Sheeley, Jonathan V Sweedler
1Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
Bioanalytical Reviews
|May 22, 2010
Summary
D-amino acid-containing peptides (DAACPs) are found in animals, with altered structures enhancing biological functions. These peptides, often overlooked, may be more common than previously believed.
Area of Science:
- Biochemistry
- Molecular Biology
- Animal Physiology
Background:
- Peptides are chiral molecules, with L-amino acids forming proteins.
- D-amino acid-containing peptides (DAACPs) are found in animals, differing from bacterial peptides.
- Enzyme-catalyzed isomerization of L-amino acids to D-forms can enhance peptide function.
Purpose of the Study:
- To review the history and discovery of DAACPs in animals.
- To discuss analytical methods for separating and detecting peptide diastereomers.
- To highlight the potential prevalence of DAACPs due to subtle post-translational modifications.
Main Methods:
- Review of existing literature on DAACPs.
- Discussion of analytical techniques for diastereomeric separation and detection.
- Analysis of discrepancies in bioassays and chromatography indicating DAACPs.
Main Results:
- DAACPs have been identified across various Metazoan groups.
- The L-to-D modification is subtle and often missed by standard sequencing.
- Existing diastereomer separation techniques have aided discovery, but more robust methods are needed.
Conclusions:
- DAACPs may be more widespread in animals than currently recognized.
- Improved analytical methods are crucial for identifying DAACPs in complex biological samples.
- Understanding DAACPs is vital for comprehending their enhanced biological roles.
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