• Journal of Microbiology and Biotechnology
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• 제13권3호
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• pp.344-347
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• 2003

Unnatural amino acid S-(2-nitrobenzyl)cysteine was incorporated into human erythropoietin by using a programmed suppression of nonsense codon in a cell-free protein synthesis system. Several controlling factors affecting the operational efficiency of the suppression were investigated and optimized. The amount of suppressor tRNA and the concentration of $Mg^2+$ were crucial not only for the efficiency but also for the control of the exact suppression. In addition, some general optimization factor are reported in order to improve the efficiency in an unnatural amino acid mutagenesis.