title: Conformational flexibility of RecA protein filament: transitions between compressed and stretched states.
abstract: RecA protein is a central enzyme in homologous DNA recombination, repair and other forms of DNA metabolism in bacteria. It functions as a flexible helix-shaped filament bound on stretched single-stranded or double-stranded DNA in the presence of ATP. In this work, we present an atomic level model for conformational transitions of the RecA filament. The model describes small movements of the RecA N-terminal domain due to coordinated rotation of main chain dihedral angles of two amino acid residues (Psi/Lys23 and Phi/Gly24), while maintaining unchanged the RecA intersubunit interface. The model is able to reproduce a wide range of observed helix pitches in transitions between compressed and stretched conformations of the RecA filament. Predictions of the model are in agreement with Small Angle Neutron Scattering (SANS) measurements of the filament helix pitch in RecA::ADP-AlF(4) complex at various salt concentrations.
authors.affiliation: Division of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute, the Russian Academy of Sciences, Gatchina/St. Petersburg, Russia. pmg@omrb.pnpi.spb.ru
authors.forename: Michael
authors.initials: M
authors.lastname: Petukhov
authors.forename: Dmitry
authors.initials: D
authors.lastname: Lebedev
authors.forename: Valery
authors.initials: V
authors.lastname: Shalguev
authors.forename: Akhmed
authors.initials: A
authors.lastname: Islamov
authors.forename: Aleksandr
authors.initials: A
authors.lastname: Kuklin
authors.forename: Vladislav
authors.initials: V
authors.lastname: Lanzov
authors.forename: Vladimir
authors.initials: V
authors.lastname: Isaev-Ivanov
mesh_terms: D000596:Amino Acids / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D019281:Dimerization; D004926:Escherichia coli / Q000737:chemistry* / Q000235:genetics; D008958:Models, Molecular; D018583:Pliability; D011485:Protein Binding; D011487:Protein Conformation; D011938:Rec A Recombinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D012965:Sodium Chloride; D055672:Static Electricity
chemical_list: D000596:Amino Acids; D012965:Sodium Chloride; D011938:Rec A Recombinases