Open AccessSynthesis and Site-Specific Incorporation of Red-Shifted Azobenzene Amino Acids into Proteins
Author(s) -
Alford A. John,
Carlo P. Ramil,
Yulin Tian,
Gang Cheng,
Qing Lin
Publication year - 2015
Publication title -
organic letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.94
H-Index - 239
eISSN - 1523-7060
pISSN - 1523-7052
DOI - 10.1021/acs.orglett.5b03268
Subject(s) - azobenzene , chemistry , amino acid , alanine , fluorescence , transfer rna , mutant , tyrosine , ceric ammonium nitrate , stereochemistry , photochemistry , molecule , organic chemistry , biochemistry , polymer , copolymer , gene , rna , physics , quantum mechanics
A series of red-shifted azobenzene amino acids were synthesized in moderate-to-excellent yields via a two-step procedure in which tyrosine derivatives were first oxidized to the corresponding quinonoidal spirolactones followed by ceric ammonium nitrate-catalyzed azo formation with the substituted phenylhydrazines. The resulting azobenzene-alanine derivatives exhibited efficient trans/cis photoswitching upon irradiation with a blue (448 nm) or green (530 nm) LED light. Moreover, nine superfolder green fluorescent protein (sfGFP) mutants carrying the azobenzene-alanine analogues were expressed in E. coli in good yields via amber codon suppression with an orthogonal tRNA/PylRS pair, and one of the mutants showed durable photoswitching with the LED light.