title: AUREMOL-RFAC-3D, combination of R-factors and their use for automated quality assessment of protein solution structures.
abstract: We present here the computer program AUREMOL-RFAC-3D that is a generalization of the previously published program RFAC for the fully automated estimation of residual indices (R-factors) from 2D NOESY spectra. It is part of the larger AUREMOL software package (www.auremol.de). RFAC-3D calculates R-factors directly from two-dimensional homonuclear NOESY spectra as well as from three-dimensional (15)N or (13)C edited NOESY-HSQC spectra and thus extends the application range to larger proteins. The fully automated method includes automated peak picking and integration, a Bayesian noise and artifact recognition and the use of the complete relaxation matrix formalism. To enhance the reliability of the calculated R-factors the method is also generalized to calculate combined R-factors from a set of 2D and 3D-spectra. For an optimal combination of the information derived from different sources a plausible formalism had to be derived. In addition, we present a novel direct R-factors based measure that correlates an R-factors as defined in this paper to the root mean square deviation of the actual structure from the optimal structure. The new program has been successfully tested on the histidine containing phosphocarrier protein (HPr) from Staphylococcus carnosus and on the Ras-binding domain (RBD) of the Ral guanine-nucleotide dissociation stimulation factor (RalGDS).
authors.affiliation: Department of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstr.31, D-93040, Regensburg, Federal Republic of Germany.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Gronwald
authors.forename: Konrad
authors.initials: K
authors.lastname: Brunner
authors.forename: Renate
authors.initials: R
authors.lastname: Kirchhöfer
authors.forename: Jochen
authors.initials: J
authors.lastname: Trenner
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Neidig
authors.forename: Hans Robert
authors.initials: HR
authors.lastname: Kalbitzer
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000032:analysis / Q000737:chemistry; D011506:Proteins / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012984:Software; D020726:ral Guanine Nucleotide Exchange Factor / Q000032:analysis / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D011506:Proteins; D020726:ral Guanine Nucleotide Exchange Factor; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C030182:phosphocarrier protein HPr