title: ProtRepeatsDB: a database of amino acid repeats in genomes.
abstract: BACKGROUND
  Genome wide and cross species comparisons of amino acid repeats is an intriguing problem in biology mainly due to the highly polymorphic nature and diverse functions of amino acid repeats. Innate protein repeats constitute vital functional and structural regions in proteins. Repeats are of great consequence in evolution of proteins, as evident from analysis of repeats in different organisms. In the post genomic era, availability of protein sequences encoded in different genomes provides a unique opportunity to perform large scale comparative studies of amino acid repeats. ProtRepeatsDB http://bioinfo.icgeb.res.in/repeats/ is a relational database of perfect and mismatch repeats, access to which is designed as a resource and collection of tools for detection and cross species comparisons of different types of amino acid repeats.
  
  
  METHODS
  ProtRepeatsDB (v1.2) consists of perfect as well as mismatch amino acid repeats in the protein sequences of 141 organisms, the genomes of which are now available. The web interface of ProtRepeatsDB consists of different tools to perform repeat s; based on protein IDs, organism name, repeat sequences, and keywords as in FASTA headers, size, frequency, gene ontology (GO) annotation IDs and regular expressions (REGEXP) describing repeats. These tools also allow formulation of a variety of simple, complex and logical queries to facilitate mining and large-scale cross-species comparisons of amino acid repeats. In addition to this, the database also contains sequence analysis tools to determine repeats in user input sequences.
  
  
  CONCLUSIONS
  ProtRepeatsDB is a multi-organism database of different types of amino acid repeats present in proteins. It integrates useful tools to perform genome wide queries for rapid screening and identification of amino acid repeats and facilitates comparative and evolutionary studies of the repeats. The database is useful for identification of species or organism specific repeat markers, interspecies variations and polymorphism.
authors.affiliation: Structural and Computational Biology Group, Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India. mridulkk@icgeb.res.in
authors.forename: Mridul K
authors.initials: MK
authors.lastname: Kalita
authors.forename: Gowthaman
authors.initials: G
authors.lastname: Ramasamy
authors.forename: Sekhar
authors.initials: S
authors.lastname: Duraisamy
authors.forename: Virander S
authors.initials: VS
authors.lastname: Chauhan
authors.forename: Dinesh
authors.initials: D
authors.lastname: Gupta
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002874:Chromosome Mapping / Q000379:methods*; D003628:Database Management Systems; D030562:Databases, Protein; D006801:Humans; D016247:Information Storage and Retrieval / Q000379:methods; D008969:Molecular Sequence Data; D011506:Proteins / Q000737:chemistry* / Q000235:genetics*; D020449:Repetitive Sequences, Amino Acid; D016415:Sequence Alignment / Q000379:methods; D020539:Sequence Analysis, Protein / Q000379:methods*; D017386:Sequence Homology, Amino Acid
chemical_list: D011506:Proteins