title: Characteristic domain motion in the ribosome recycling factor revealed by 15N NMR relaxation experiments and molecular dynamics simulations.
abstract: The backbone dynamics of ribosome recycling factor (RRF) from Escherichia coli in water were characterized by (15)N NMR relaxation analysis and molecular dynamics (MD) simulation. RRF is composed of two domains connected by a joint region that consists of two peptide chains, such that the overall structure seems to mimic that of tRNA. MD trajectories indicated that the relative orientation of domains varies on the nanosecond time scale. We analyzed the observed (15)N T(1), T(2), and NOE using an extended model-free spectral density function in which the domain motions with a nanosecond time scale were considered. At 30 degrees C, the order parameters of slow motion () were determined to be approximately 0.9 for domain I and 0.7 for domain II, respectively. These values indicate that domain I is nearly fixed on the molecular diffusion frame, and domain II is wobbling in a cone for which the semi-angle is about 30 degrees.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Yoshida
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Oka
authors.forename: Susumu
authors.initials: S
authors.lastname: Uchiyama
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nakano
authors.forename: Tadayuki
authors.initials: T
authors.lastname: Kawasaki
authors.forename: Tadayasu
authors.initials: T
authors.lastname: Ohkubo
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kobayashi
mesh_terms: D004926:Escherichia coli / Q000737:chemistry; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011506:Proteins / Q000737:chemistry*; D012269:Ribosomal Proteins
chemical_list: D011506:Proteins; D012269:Ribosomal Proteins; C087267:ribosome releasing factor