Inhibition of twisting of a green fluorescent protein-like chromophore by metal complexation

Substitution of a pyridyl for the hydroxyphenyl moiety in the Green Fluorescent Protein analog p-hydroxybenzylidene-dimethylimidiazolinone produces a chromophore which turns on fluorescence in the presence of Zn(2+) or Cd(2+) ions. Such a phenomenon provides proof of principle for using GFP chromophores in a variety of sensing applications.