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Amino acids: chemistry, functionality and selected non-enzymatic post-translational modifications.
Rainer Bischoff1, Hartmut Schlüter
1University of Groningen, Department of Pharmacy, Analytical Biochemistry, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands. r.p.h.bischoff@rug.nl
Journal of Proteomics
|March 6, 2012
Summary
Proteomics aims to fully characterize proteins, but discovering all amino acid modifications requires understanding side chain chemistry. This tutorial explores non-enzymatic modifications to aid in identifying unknown protein derivatives.
Area of Science:
- Biochemistry
- Proteomics
- Chemical Biology
Background:
- The complete characterization of protein species in biological samples remains a significant challenge in proteomics.
- Current analytical and data analysis methods, along with the discovery of novel amino acid modifications, limit the achievement of this goal.
- Understanding amino acid side chain chemistry is crucial for detecting known and discovering unknown modified side chains.
Purpose of the Study:
- To provide an in-depth tutorial on the chemistry of amino acid side chains, focusing on non-enzymatic modifications.
- To highlight the diversity of modified amino acids through exemplary reactions.
- To introduce a standardized terminology for describing the complete chemical composition of protein species, including sequence and modifications.
Main Methods:
- Focus on the fundamental chemistry of reactive groups within amino acid side chains.
- Illustrate diverse non-enzymatic amino acid modifications with specific chemical reaction examples.
- Introduce a systematic nomenclature for describing protein composition and post-translational modifications.
Main Results:
- Demonstrates the vast diversity of naturally occurring amino acid modifications.
- Provides insights into the chemical principles underlying side chain modifications.
- Equips readers with the knowledge to recognize and describe a wide range of protein modifications.
Conclusions:
- A comprehensive understanding of amino acid chemistry is essential for advancing proteomics.
- Awareness of non-enzymatic modifications and their chemistry is key to discovering novel protein derivatives.
- Standardized terminology will facilitate accurate and complete reporting of protein species composition.
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These groups modify specific amino acids in a protein.
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These groups modify specific amino acids in a protein.
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Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.
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Glycosylation occurs in...
Glycosylation occurs in...