title: ProtBuD: a database of biological unit structures of protein families and superfamilies.
abstract: BACKGROUND
  Modeling of protein interactions is often possible from known structures of related complexes. It is often time-consuming to find the most appropriate template. Hypothesized biological units (BUs) often differ from the asymmetric units and it is usually preferable to model from the BUs.
  
  
  RESULTS
  ProtBuD is a database of BUs for all structures in the Protein Data Bank (PDB). We use both the PDBs BUs and those from the Protein Quaternary Server. ProtBuD is searchable by PDB entry, the Structural Classification of Proteins (SCOP) designation or pairs of SCOP designations. The database provides the asymmetric and BU contents of related proteins in the PDB as identified in SCOP and Position-Specific Iterated BLAST (PSI-BLAST). The asymmetric unit is different from PDB and/or Protein Quaternary Server (PQS) BUs for 52% of X-ray structures, and the PDB and PQS BUs disagree on 18% of entries.
  
  
  BACKGROUND
  The database is provided as a standalone program and a web server from http://dunbrack.fccc.edu/ProtBuD.php.
authors.affiliation: Institute for Cancer Research, Fox Chase Cancer Center 333 Cottman Avenue, Philadelphia, PA 19111 USA.
authors.forename: Qifang
authors.initials: Q
authors.lastname: Xu
authors.forename: Adrian
authors.initials: A
authors.lastname: Canutescu
authors.forename: Zoran
authors.initials: Z
authors.lastname: Obradovic
authors.forename: Roland L
authors.initials: RL
authors.lastname: Dunbrack
mesh_terms: D000595:Amino Acid Sequence; D003628:Database Management Systems; D030562:Databases, Protein; D016247:Information Storage and Retrieval / Q000379:methods*; D008969:Molecular Sequence Data; D011506:Proteins / Q000737:chemistry* / Q000145:classification / Q000378:metabolism*; D016415:Sequence Alignment / Q000379:methods; D020539:Sequence Analysis, Protein / Q000379:methods*; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D014584:User-Computer Interface
chemical_list: D011506:Proteins