D406 Nucleic Acids Research, 2008, Vol. 36, Database issue Figure 2. Summary page for the metabolite N-acetyl-L-glutamine from the BMRB metabolomics website. In each case, the resulting structures were compared with the originals to assess current NMR structure calculation protocols. Metabolomics standard compounds BMRB maintains an archive of NMR spectral data for metabolomic compounds. The current standard com- pound data have been provided by the Madison Metabolomic Consortium (MMC). Annotated data for over 270 compounds are available with 1H 1D, 13C 1D, 13C 908 DEPT. 13C 1358 DEPT, 1H-1H TOCSY and 1H-13C HSQC natural abundance spectra present for most compounds (Figure 2). Peak lists, spectral transition lists, images of the spectra and assigned peak lists are being added to the archive. BMRB will accept NMR data for metabolites from any group interested in making a deposition. The archive can be queried for data on speciﬁc compounds by name, KEGG ID, PubChem compound or substance ID and PDB ID. 1H, 13C or paired 1H-13C spectral peak lists taken from spectral of biological samples can be used to query for compounds with matching properties. An ordered list of matching com- pounds is returned prioritized with the best match at the top of the list and linked to a visual presentation of the chemical shift alignments for the subject data and the compounds returned by the query. A list of mass values also can be used to query the archive and retrieve compounds that have mass values within deﬁned limits. Time-domain data For the past few years, BMRB has been archiving and making available sets of raw spectral time-domain data collected from the NMR experiments carried out to derive assigned chemical shifts provided in BMRB entries and the restraints used to calculate atomic structures deposited at the wwPDB. Data sets of this kind, which now number more than 65 entries, are welcome from any research group. Most of the original entries were contributed by two groups funded by the NIH Protein Structure Initiative: the Northeast Structural Genomics Consortium (NESG) and the Center for Eukaryotic Structural Genomics (CESG). Recently, the ﬁrst set of time-domain data for NOESY spectra used in the determination of an RNA structure were deposited by Butcher and coworkers [(35); BMRB accession code 15417]. All of these datasets are listed on the BMRB website (http://www.bmrb. wisc.edu/data_library/timedomain/), and links can be found on the summary page for those entries that have associated time-domain data. Data for over 500 NMR experiments are included, representing more than 100