Exploration of new chromophore structures leads to the identification of improved blue fluorescent proteins

Biochemistry. 2007 May 22;46(20):5904-10. doi: 10.1021/bi700199g. Epub 2007 Apr 20.


The variant of Aequorea green fluorescent protein (GFP) known as blue fluorescent protein (BFP) was originally engineered by substituting histidine for tyrosine in the chromophore precursor sequence. Herein we report improved versions of BFP along with a variety of engineered fluorescent protein variants with novel and distinct chromophore structures that all share the property of a blue fluorescent hue. The two most intriguing of the new variants are a version of GFP in which the chromophore does not undergo excited-state proton transfer and a version of mCherry with a phenylalanine-derived chromophore. All of the new blue fluorescing proteins have been critically assessed for their utility in live cell fluorescent imaging. These new variants should greatly facilitate multicolor fluorescent imaging by legitimizing blue fluorescing proteins as practical and robust members of the fluorescent protein "toolkit".

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anthozoa / chemistry
  • Anthozoa / genetics
  • Green Fluorescent Proteins / chemistry*
  • Green Fluorescent Proteins / genetics
  • Hydrozoa / chemistry
  • Hydrozoa / genetics
  • Luminescent Proteins / chemistry*
  • Luminescent Proteins / genetics
  • Mutagenesis, Site-Directed
  • Spectrometry, Fluorescence
  • Spectrophotometry, Ultraviolet
  • Tyrosine / chemistry


  • Luminescent Proteins
  • blue fluorescent protein, Aequorea victoria
  • enhanced green fluorescent protein
  • red fluorescent protein
  • Green Fluorescent Proteins
  • Tyrosine