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Amino acid analysis.
J W Crabb1, K A West, W S Dodson
1W. Alton Jones Cell Science Center, Lake Placid, New York, USA.
Current Protocols in Protein Science
|April 23, 2008
Summary
Phenylthiocarbamyl amino acid analysis (PTC-AAA) offers a budget-friendly method for quantifying peptides and proteins at the picomole level. This guide details essential protocols for establishing this sensitive technique.
Area of Science:
- Biochemistry
- Analytical Chemistry
Background:
- Amino acid analysis (AAA) is crucial for protein and peptide quantification.
- Two primary methods exist: postcolumn derivatization with ion-exchange chromatography and precolumn derivatization with reversed-phase HPLC (RP-HPLC).
Purpose of the Study:
- To detail the phenylthiocarbamyl amino acid analysis (PTC-AAA) method for picomole-level quantification.
- To provide a guide for establishing AAA technology on a modest budget.
Main Methods:
- Focuses on precolumn derivatization using phenylthiocarbamyl (PTC) chemistry.
- Describes derivatization and analysis conditions for PTC-AAA.
- Includes protocols for sample preparation, hydrolysis, and instrument calibration.
Main Results:
- Provides conditions for PTC derivatization and analysis.
- Addresses analysis of challenging amino acid residues like cysteine and tryptophan.
- Offers techniques for phosphoamino acids and hydroxyproline.
Conclusions:
- PTC-AAA is a viable and popular method for sensitive amino acid quantification.
- The described protocols facilitate the establishment of AAA technology, even with limited resources.
- The method supports the analysis of standard and unusual amino acid residues.
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