Crystallographic evidence of a large ligand-induced hinge-twist motion between the two domains of the maltodextrin binding protein involved in active transport and chemotaxis.Sharff, A.J., Rodseth, L.E., Spurlino, J.C., Quiocho, F.A.
(1992) Biochemistry 31: 10657-10663
- PubMed: 1420181
- PubMed Abstract:
- The 2.3 Angstroms Resolution Structure of the Maltose-or Maltodextrin-Binding Protein, a Primary Receptor of Bacterial Active Transport and Chemotaxis
Spurlino, J.C.,Lu, G.-Y.,Quiocho, F.A.
(1991) J.Biol.Chem. 266: 5202
- Three Dimensional Structure of Recombinant Human Muscle Fatty Acid Binding Protein
Zanotti, G.,Scapin, G.,Spadon, P.,Veerkamp, J.H.,Sacchettini, J.C.
(1992) J.Biol.Chem. 267: 18541
The periplasmic maltodextrin binding protein of Escherichia coli serves as an initial receptor for the active transport of and chemotaxis toward maltooligosaccharides. The three-dimensional structure of the binding protein complexed with maltose has ...
The periplasmic maltodextrin binding protein of Escherichia coli serves as an initial receptor for the active transport of and chemotaxis toward maltooligosaccharides. The three-dimensional structure of the binding protein complexed with maltose has been previously reported [Spurlino, J. C., Lu, G.-Y., & Quiocho, F. A. (1991) J. Biol. Chem. 266, 5202-5219]. Here we report the structure of the unliganded form of the binding protein refined to 1.8-A resolution. This structure, combined with that for the liganded form, provides the first crystallographic evidence that a major ligand-induced conformational change occurs in a periplasmic binding protein. The unliganded structure shows a rigid-body "hinge-bending" between the two globular domains by approximately 35 degrees, relative to the maltose-bound structure, opening the sugar binding site groove located between the two domains. In addition, there is an 8 degrees twist of one domain relative to the other domain. The conformational changes observed between this structure and the maltose-bound structure are consistent with current models of maltose/maltodextrin transport and maltose chemotaxis and solidify a mechanism for receptor differentiation between the ligand-free and ligand-bound forms in signal transduction.
Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas 77030.