title: Crystal structures of wild-type Trichoderma reesei Cel7A catalytic domain in open and closed states.
abstract: Trichoderma reesei Cel7A efficiently hydrolyses cellulose. We report here the crystallographic structures of the wild-type TrCel7A catalytic domain (CD) in an open state and, for the first time, in a closed state. Molecular dynamics (MD) simulations indicate that the loops along the CD tunnel move in concerted motions. Together, the crystallographic and MD data suggest that the CD cycles between the tense and relaxed forms that are characteristic of work producing enzymes. Analysis of the interactions formed by R251 provides a structural rationale for the concurrent decrease in product inhibition and catalytic efficiency measured for product-binding site mutants.
authors.affiliation: Molecular and Structural Biochemistry Department, North Carolina State University, Raleigh, NC, USA.|Neutron Sciences Directorate, Oak Ridge National Laboratory, TN, USA.
authors.forename: Annette M
authors.initials: AM
authors.lastname: Bodenheimer
authors.affiliation: Molecular and Structural Biochemistry Department, North Carolina State University, Raleigh, NC, USA.|Neutron Sciences Directorate, Oak Ridge National Laboratory, TN, USA.
authors.forename: Flora
authors.initials: F
authors.lastname: Meilleur
mesh_terms: D001665:Binding Sites; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D006026:Glycoside Hydrolases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D056004:Molecular Dynamics Simulation; D009154:Mutation; D014242:Trichoderma / Q000201:enzymology*
chemical_list: D006026:Glycoside Hydrolases
keywords: 
  Trichoderma reesei
  ; Cel7A; cellulase; closed state; processivity; product-binding site