Synthesis of fluorescent dipeptidomimetics and their ribosomal incorporation into green fluorescent protein.
The synthesis and incorporation into position 66 of green fluorescent protein (GFP) by in vitro protein translation of novel oxazole and thiazole based dipeptidomimetics are described. The compounds may be regarded as GFP chromophore analogues, and are strongly fluorescent. An α-amido-β-ketoester intermediate was obtained via bisacylation of a protected glycine. The intermediate underwent dehydrative cyclization to afford the 1,3-oxazole and was treated with Lawesson's reagent to furnish the 1,3-thiazole. When these fluorophores were introduced into position 66 of GFP in place of Tyr66, the resulting GFP analogues exhibited fluorescence emission several-fold greater than wild-type GFP; the emission was also shifted to shorter wavelength. It may be noted that compared to the typical fluorophores formed in the natural and modified fluorescent proteins, the oxazole and thiazole fluorophores are completely stable and do not require activation by posttranslational modification to exhibit fluorescence.
Center for BioEnergetics, Biodesign Institute, and Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA.
Sandipan
S
Roy Chowdhury
Center for BioEnergetics, Biodesign Institute, and Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA.
Rumit
R
Maini
Center for BioEnergetics, Biodesign Institute, and Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA.
Larisa M
LM
Dedkova
Center for BioEnergetics, Biodesign Institute, and Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA. Electronic address: Sidney.Hecht@asu.edu.
Sidney M
SM
Hecht
D005453:Fluorescence; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000737:chemistry* / Q000378:metabolism*; D015394:Molecular Structure; D057786:Peptidomimetics / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*
D005456:Fluorescent Dyes; D057786:Peptidomimetics; D049452:Green Fluorescent Proteins
Dipeptidomimetics; Green fluorescent protein; Modified ribosome; Oxazole; Thiazole