Structural and thermal stability characterization of Escherichia coli D-galactose/D-glucose-binding protein.

The effect of temperature and glucose binding on the structure of the galactose/glucose-binding protein from Escherichia coli was investigated by circular dichroism, Fourier transform infrared spectroscopy, and steady-state and time-resolved fluorescence. The data showed that the glucose binding induces a moderate change of the secondary structure content of the protein and increases the protein thermal stability. The infrared spectroscopy data showed that some protein stretches, involved in alpha-helices and beta strand conformations, are particularly sensitive to temperature.