Cloning, Purification, Crystallization and Preliminary X-Ray Diffraction Studies of Periplasmic Glucose Binding Protein of <i>Pseudomonas putida</i> CSV86

Abstract

Biochemical data and genomic analysis indicate the involvement of a putative ABC transporter for glucose transport in Pseudomonas putida CSV86. The periplasmic solute binding proteins are known to confer substrate specificity to the ABC transporters by binding specifically to the substrate and transferring them to their cognate inner membrane transport assembly. Periplasmic glucose binding protein from Pseudomonas putida CSV86 (ppGBP) was found to be glucose specific. The gene encoding ppGBP was cloned. Recombinant ppGBP was overexpressed and purified to homogeneity. The purified recombinant protein showed glucose binding activity of 752 pmol/mg of protein and was crystallized as a complex with glucose. The crystal diffracted to 1.7 &Aring resolution using home X-ray source. Preliminary analysis of diffraction data showed that the crystals belonged to space group P 2 1 2 1 2 with unit-cell parameters a = 102.56, b = 119.2, c = 66.65 &Aring and α = β = γ = 90&deg. Matthews coefficient calculation showed the presence of two molecules in the asymmetric unit with solvent content of 45.7%.