title: Observation of RecA protein monomer by small angle X-ray scattering with synchrotron radiation.
abstract: RecA protein is capable of forming homo-oligomers in solution. The oligomeric and monomeric states of Thermus thermophilus RecA protein were studied by small angle X-ray scattering, a direct method used to measure the overall dimensions of a macromolecule. In the presence of 3 M urea or 0.2 M lithium perchlorate, RecA dissociates from higher oligomeric states to form a hexamer with a radius of gyration (R(g)) of 52 A. The value of R(g) decreased to 36 A at a higher lithium perchlorate concentration (1.0 M). The zero angle intensity, I(0), was consistent with the identification of the former state as a hexamer and the latter as a monomer.
authors.affiliation: Department of Biology, Graduate School of Science, Osaka University, Toyonaka, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Kato
authors.forename: M
authors.initials: M
authors.lastname: Kataoka
authors.forename: T
authors.initials: T
authors.lastname: Mikawa
authors.forename: R
authors.initials: R
authors.lastname: Masui
authors.forename: N
authors.initials: N
authors.lastname: Nakagawa
authors.forename: H
authors.initials: H
authors.lastname: Kamikubo
authors.forename: S
authors.initials: S
authors.lastname: Kuramitsu
mesh_terms: D018360:Crystallography, X-Ray; D008958:Models, Molecular; D011487:Protein Conformation; D011938:Rec A Recombinases / Q000737:chemistry* / Q000528:radiation effects; D012542:Scattering, Radiation; D012984:Software; D017356:Synchrotrons; D016963:Thermus thermophilus
chemical_list: D011938:Rec A Recombinases