2FW0

Apo Open Form of Glucose/Galactose Binding Protein

Summary for 2FW0

• Entry DOI: 10.2210/pdb2fw0/pdb
• Related: 1GCG 1GLG 2GBP
• Descriptor: D-galactose-binding periplasmic protein, CALCIUM ION, SODIUM ION, ... (6 entities in total)
• Functional Keywords: periplasmic binding protein, hinge, chemotaxis, transport, ggbp, transport protein
• Biological source: Escherichia coli
• Cellular location: Periplasm: P0AEE5
• Total number of polymer chains: 1
• Total formula weight: 33812.86

Authors

Borrok, M.J.,Kiessling, L.L.,Forest, K.T. (deposition date: 2006-01-31, release date: 2007-02-06, Last modification date: 2023-08-30)

Primary citation

Borrok, M.J.,Kiessling, L.L.,Forest, K.T.
Conformational changes of glucose/galactose-binding protein illuminated by open, unliganded, and ultra-high-resolution ligand-bound structures.
Protein Sci., 16:1032-1041, 2007

PubMed Abstract: D-Glucose/D-Galactose-binding protein (GGBP) mediates chemotaxis toward and active transport of glucose and galactose in a number of bacterial species. GGBP, like other periplasmic binding proteins, can exist in open (ligand-free) and closed (ligand-bound) states. We report a 0.92 angstroms resolution structure of GGBP from Escherichia coli in the glucose-bound state and the first structure of an open, unbound form of GGBP (at 1.55 angstroms resolution). These structures vary in the angle between the two structural domains; the observed difference of 31 degrees arises from torsion angle changes in a three-segment hinge. A comparison with the closely related periplasmic receptors, ribose- and allose-binding proteins, shows that the GGBP hinge residue positions that undergo the largest conformational changes are different. Furthermore, the high-quality data collected for the atomic resolution glucose-bound structure allow for the refinement of specific hydrogen atom positions, the assignment of alternate side chain conformations, the first description of CO(2) trapped after radiation-induced decarboxylation, and insight into the role of the exo-anomeric effect in sugar binding. Together, these structures provide insight into how the hinge-bending movement of GGBP facilitates ligand binding, transport, and signaling.

PubMed: 17473016
DOI: 10.1110/ps.062707807

Experimental method

X-RAY DIFFRACTION (1.55 Å)