Abstract

Glucose sensing is used as a model to explore the advantages deriving from the use of sugar - binding proteins isolated from thermophilic organisms to develop stable fluorescence biosensors. The gene of a putative thermostable sugar-binding protein was cloned and expressed in E. coli. The recombinant protein was purified to homogeneity and used as a probe for the development of a fluorescence biosensor for the detection of glucose. Fluorescence spectroscopy experiments demonstrated that the recombinant protein binds glucose with a dissociation constant of about 10 mM, a concentration of sugar close to the concentration of glucose present in the human blood. A docking simulation on the modeled structure of the protein confirmed its ability to bind glucose and proposed possible modifications to improve the affinity for glucose and/or its detection. The obtained results suggest the use of this thermostable protein as a probe for a stable glucose biosensor.