Abstract: The present invention relates to functional, modified glucose-galactose binding proteins (GGBPs), that have a greater melting temperature (Tm) than a reference GGBP. The present invention also relates to biological sensors, e.g., glucose sensors, comprising these thermostable GGBPs. The present invention also relates to nucleic acids encoding these thermostable GGBPs.

Abstract: The current invention relates to fusion proteins comprising at least one functional periplasmic binding protein, at least one labeling moiety and at least one fluorescent protein. In one embodiment, the periplasmic binding protein is a functional glucose-galactose binding protein (GGBP). The invention also relates to methods for quantifying an analyte, for example glucose, in a cell or tissue comprising administering a composition comprising a fluorescent periplasmic binding fusion protein portion to the cell or tissue, and measuring the fluorescence of the fluorescent periplasmic binding fusion protein.

Abstract: The invention is directed to compositions of mutated binding proteins containing reporter groups, analyte biosensor devices derived therefrom, and their use as analyte biosensors both in vitro and in vivo.

Abstract: The present invention relates to methods of screening or isolating stable mutant binding proteins from a protein library of mutant proteins. The methods comprise culturing host cells under conditions suitable for protein expression. The collection of host cells comprise collectively a set of expression vectors, and this collection of expression vectors encodes the various members of a protein library of mutant binding proteins. The cultured cells, harboring the expression vectors, are contacted with a ligand, and differences in interaction, among the individual host cells, with the ligand are detected. The individual host cells displaying the desired interaction with the ligand are then separated from individual host cells that do not display the desired interaction with the ligand.

Abstract: The current invention relates to fusion proteins comprising at least one functional periplasmic binding protein, at least one labeling moiety and at least one fluorescent protein. In one embodiment, the periplasmic binding protein is a functional glucose-galactose binding protein (GGBP). The invention also relates to methods for quantifying an analyte, for example glucose, in a cell or tissue comprising administering a composition comprising a fluorescent periplasmic binding fusion protein portion to the cell or tissue, and measuring the fluorescence of the fluorescent periplasmic binding fusion protein.

Abstract: A device for sensing analyte concentration, and in particular glucose concentration, in vivo or in vitro is disclosed. An optical conduit, preferably an optical fiber has an optical system at the proximal end of the optical conduit. A sensing element is attached to the distal end of the optical conduit, and comprises at least one binding protein adapted to bind with at least one target analyte. The sensing element further comprises at least one reporter group that undergoes a luminescence change with changing analyte concentrations. Optionally, the sensing element includes reference groups with luminescence properties that are substantially unchanged by variations in the analyte concentrations.

Abstract: The invention is directed to compositions of mutated binding proteins containing reporter groups, analyte biosensor devices derived therefrom, and their use as analyte biosensors both in vitro and in vivo.