D402–D408 Nucleic Acids Research, 2008, Vol. 36, Database issue doi:10.1093/nar/gkm957 BioMagResBank Eldon L. Ulrich1,*, Hideo Akutsu 2 , Jurgen F. Doreleijers1, Yoko Harano 2 , Yannis E. Ioannidis3, Jundong Lin1, Miron Livny4, Steve Mading 1 , Dimitri Maziuk 1 , Zachary Miller4, Eiichi Nakatani2, Christopher F. Schulte1, David E. Tolmie1, R. Kent Wenger4, Hongyang Yao1 and John L. Markley1 1Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA, 2Institute for Protein Research, Osaka University, Osaka, Japan, 3The Department of Informatics, University of Athens, Athens, Greece and 4Department of Computer Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA Received September 14, 2007; Revised October 15, 2007; Accepted October 16, 2007 Published online 4 November 2007 ABSTRACT The BioMagResBank (BMRB: www.bmrb.wisc.edu) is a repository for experimental and derived data gathered from nuclear magnetic resonance (NMR) spectroscopic studies of biological molecules. BMRB is a partner in the Worldwide Protein Data Bank (wwPDB). The BMRB archive consists of four main data depositories: (i) quantitative NMR spectral parameters for proteins, peptides, nucleic acids, carbohydrates and ligands or cofactors (assigned chemical shifts, coupling constants and peak lists) and derived data (relaxation param- eters, residual dipolar couplings, hydrogen exchange rates, pKa values, etc.), (ii) databases for NMR restraints processed from original author depositions available from the Protein Data Bank, (iii) time-domain (raw) spectral data from NMR experiments used to assign spectral resonances and determine the structures of biological macro- molecules and (iv) a database of one- and two- dimensional 1H and 13C one- and two-dimensional NMR spectra for over 250 metabolites. The BMRB website provides free access to all of these data. BMRB has tools for querying the archive and retrieving information and an ftp site (ftp. bmrb.wisc.edu) where data in the archive can be downloaded in bulk. Two BMRB mirror sites exist: one at the PDBj, Protein Research Institute, Osaka University, Osaka, Japan (bmrb. protein.osaka-u.ac.jp) and the other at CERM, University of Florence, Florence, Italy (bmrb. postgenomicnmr.net/). The site at Osaka also accepts and processes data depositions. INTRODUCTION Nuclear magnetic resonance (NMR) spectroscopy is unique among biophysical approaches in its ability to provide a broad range of atomic-level information relevant to the structural, dynamic and chemical proper- ties of biological macromolecules. Newly developed NMR techniques (1–3) are enabling the collection of NMR data from increasingly larger systems, including membrane bound biopolymers. BioMagResBank (4,5) (BMRB, www.bmrb.wisc.edu) is designed to empower structural biologists, macromolecular chemists and other scientists who use these data to address questions concerning a variety of macromolecular phenomena, including macromolecular recognition, enzyme reaction mechanisms, macromolecular ligand interactions, protein conformational stability, protein folding pathways and nucleic acid conformations. The database consists of four large archives: (i) over 4500 entries containing NMR spectral values and derived information (assigned chemi- cal shifts, coupling constants, relaxation parameters, residual dipolar couplings, etc.); these are cross-referenced to 3D structures in the PDB as available. (ii) The NMR Restraints Grid, a relational database for NMR restraints sets that is continually updated as new entries are released at the PDB (6,7). (iii) An archive of multi-dimensional, time-domain NMR data associated with structural studies of proteins and nucleic acids. (iv) A database containing time-domain NMR spectral data, spectral images, spectral peak lists and assigned chemical shifts for more than 250 metabolites. The goals in several laboratories around the world are to streamline procedures for structure determination from NMR data and to develop ways to improve the quality of structures. Promising approaches include the automation of NMR peak assignments (8–10) and computerized sorting of ambiguous structural restraints (11–13). *To whom correspondence should be addressed. Tel: +1 608 265 5741; Fax: +1 608 262 3453; Email: elu@bmrb.wisc.edu 2007 The Author(s) This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.