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Updated: May 3, 2026

Site Specific Lysine Acetylation of Histones for Nucleosome Reconstitution using Genetic Code Expansion in Escherichia coli
Published on: December 26, 2020
Genetic incorporation of histidine derivatives using an engineered pyrrolysyl-tRNA synthetase
Han Xiao1, Francis B Peters, Peng-Yu Yang
1Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.
Abstract:
A polyspecific amber suppressor aminoacyl-tRNA synthetase/tRNA pair was evolved that genetically encodes a series of histidine analogues in both Escherichia coli and mammalian cells. In combination with tRNACUA(Pyl), a pyrrolysyl-tRNA synthetase mutant was able to site-specifically incorporate 3-methyl-histidine, 3-pyridyl-alanine, 2-furyl-alanine, and 3-(2-thienyl)-alanine into proteins in response to an amber codon. Substitution of His66 in the blue fluorescent protein (BFP) with these histidine analogues created mutant proteins with distinct spectral properties. This work further expands the structural and chemical diversity of unnatural amino acids (UAAs) that can be genetically encoded in prokaryotic and eukaryotic organisms and affords new probes of protein structure and function.
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