Incorporation of Unnatural Non-α-Amino Acids into the N-Terminus of Proteins in a Cell-Free Translation System

  • Takahiro HohsakaEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 794)


Unnatural amino acid mutagenesis allows us to introduce unnatural α-amino acids into internal positions of proteins in response to expanded codons such as amber and four-base codons. To improve the unnatural amino acid mutagenesis, the incorporation of unnatural α-amino acids and non-α-amino acids into the N-terminus of proteins has been achieved using expanded initiation codons. Here, we describe the method for the incorporation of fluorescent-labeled non-α-amino acids into the N-terminus of proteins in a cell-free translation system.

Key words

Unnatural amino acid Translation initiation Cell-free translation Chemical aminoacylation N-terminal labeling Fluorescence labeling 



This work was supported by Grants-in-Aid for Exploratory Research (17651122) and Scientific Research on Innovative Areas (20107005) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.School of Materials ScienceJapan Advanced Institute of Science and TechnologyNomiJapan

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