title: SIMAP--the similarity matrix of proteins.
abstract: BACKGROUND
  Sequence similarity searches are of great importance in bioinformatics. Exhaustive searches for homologous proteins in databases are computationally expensive and can be replaced by a database of pre-calculated homologies in many cases. Retrieving similarities from an incrementally updated database instead of repeatedly recalculating them should provide homologs much faster and frees computational resources for other purposes.
  
  
  RESULTS
  We have implemented SIMAP-a database containing the similarity space formed by almost all amino acid sequences from public databases and completely sequenced genomes. The database is capable of handling very large datasets and allows incremental updates. We have implemented a powerful backbone for similarity computation, which is based on FASTA heuristics. By providing WWW interfaces as well as web services, we make our data accessible to the worldwide community. We have also adapted procedures to detect putative orthologs as example applications.
  
  
  BACKGROUND
  The SIMAP portal page providing links to SIMAP services is publicly available: http://mips.gsf.de/services/analysis/simap/. The web services can be accessed under http://mips.gsf.de/proj/hobitws/services/RPCSimapService?wsdl and http://mips.gsf.de/proj/hobitws/services/DocSimapService?wsdl
authors.affiliation: Institute for Bioinformatics, GSF-National Research Center for Environment and Health Ingolstädter, Neuherberg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Arnold
authors.forename: Thomas
authors.initials: T
authors.lastname: Rattei
authors.forename: Patrick
authors.initials: P
authors.lastname: Tischler
authors.forename: Minh-Duc
authors.initials: MD
authors.lastname: Truong
authors.forename: Volker
authors.initials: V
authors.lastname: Stümpflen
authors.forename: Werner
authors.initials: W
authors.lastname: Mewes
mesh_terms: D000465:Algorithms; D000595:Amino Acid Sequence; D003198:Computer Simulation; D003628:Database Management Systems; D030562:Databases, Protein; D016247:Information Storage and Retrieval / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011506:Proteins / Q000737:chemistry* / Q000648:ultrastructure; D016415:Sequence Alignment / Q000379:methods*; D020539:Sequence Analysis, Protein / Q000379:methods*; D017386:Sequence Homology, Amino Acid; D012984:Software; D014584:User-Computer Interface
chemical_list: D011506:Proteins