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Published on: November 15, 2017
N-terminal sequence analysis of proteins and peptides
Kaye D Speicher1, Nicole Gorman1, David W Speicher1
1The Wistar Institute, Philadelphia, Pennsylvania.
Current Protocols in Protein Science
|August 19, 2009
Summary
Automated N-terminal sequencing analyzes amino acid sequences of proteins. Despite mass spectrometry advances, it remains vital for specific protein characterization and modification mapping.
Area of Science:
- Biochemistry
- Proteomics
- Analytical Chemistry
Background:
- Automated N-terminal sequencing is a chemical process for determining amino acid sequences.
- It requires picomole quantities of purified peptides or proteins with unmodified N-termini.
- Mass spectrometry has reduced the demand for N-terminal sequencing in some applications.
Purpose of the Study:
- To highlight the continued relevance of N-terminal sequencing.
- To define specific applications where N-terminal sequencing is superior.
- To provide context on its role in protein analysis.
Main Methods:
- Chemical derivatization and sequential amino acid removal from the N-terminus.
- Analysis of purified peptides or intact proteins.
- Quantification of required sample amounts (picomoles).
Main Results:
- N-terminal sequencing remains essential for specific protein analyses.
- It is the preferred method for verifying recombinant protein N-termini.
- It is crucial for identifying proteins from unsequenced genomes and mapping refractory modifications.
Conclusions:
- N-terminal sequencing retains critical applications in proteomics.
- Its utility persists for recombinant protein verification and complex modification analysis.
- It complements mass spectrometry for comprehensive protein characterization.
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