A fluorobody is a manmade hybrid molecule that is composed of green fluorescent protein (GFP) and a fragment of antibody, which combines the affinity and specificity of an antibody with the visibility of a GFP. It is able to provide a real-time indication of binding while avoiding the use of tags and secondary binding reagents. Here, the expression, purification and crystal structure of a recombinant fluorobody for TLH (thermolabile haemolysin), a toxin from the lethal food-borne disease bacteriumVibrio parahaemolyticus, are presented. This is the first structure of a fluorobody to be reported. Crystals belonging to space groupP43212, with unit-cell parametersa=b= 63.35,c = 125.90 Å, were obtained by vapour diffusion in hanging drops and the structure was refined to anRfreeof 16.7% at 1.5 Å resolution. The structure shows a CDR loop of the antibody on the GFP scaffold.
Crystal Structure of Green Fluorescent Protein Clover and Design of Clover-Based Redox Sensors