title: Structural and thermal stability characterization of Escherichia coli D-galactose/D-glucose-binding protein.
abstract: 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. The fluorescence studies showed that the intrinsic tryptophanyl fluorescence of the protein is well represented by a three-exponential model and that in the presence of glucose the protein adopts a structure less accessible to the solvent. The new insights on the structural properties of the galactose/glucose-binding protein can contribute to a better understanding of the protein functions and represent fundamental information for the development of biotechnological applications of the protein.
authors.affiliation: University of Maryland at Baltimore, Center for Fluorescence Spectroscopy, 725 W Lombard Street, Baltimore Maryland 21201, USA. dauria@dafne.ibpe.na.cnr.it
authors.forename: Sabato
authors.initials: S
authors.lastname: D'Auria
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Alfieri
authors.forename: Maria
authors.initials: M
authors.lastname: Staiano
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Pelella
authors.forename: Mose'
authors.initials: M
authors.lastname: Rossi
authors.forename: Andrea
authors.initials: A
authors.lastname: Scirè
authors.forename: Fabio
authors.initials: F
authors.lastname: Tanfani
authors.forename: Enrico
authors.initials: E
authors.lastname: Bertoli
authors.forename: Zigmunt
authors.initials: Z
authors.lastname: Grycznyski
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Lakowicz
mesh_terms: D003198:Computer Simulation; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000032:analysis* / Q000737:chemistry*; D008958:Models, Molecular; D009004:Monosaccharide Transport Proteins / Q000032:analysis* / Q000737:chemistry*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D013696:Temperature
chemical_list: D029968:Escherichia coli Proteins; D009004:Monosaccharide Transport Proteins