Computer Storage of Sequences. (Chapter 2 of Bioinformatics: Sequence and Genome Analysis By David W. Mount). CSE730: Seminar on “Information Retrieval of Biomedical Text and Data”. Outline. Storing DNA/Protein sequences into computer files or databases.
Computer Storage of Sequences (Chapter 2 of Bioinformatics: Sequence and Genome Analysis By David W. Mount) CSE730: Seminar on “Information Retrieval of Biomedical Text and Data”
Outline • Storing DNA/Protein sequences into computer files or databases. • Related information placed in the database along with the sequence in a number of sequence data formats. • Online public access Databases for sequence retrieval.
Sequence Formats Sequence is stored as ASCII text (i.e. sequence of A,G,C,T…) along with annotations. Different sequence formats recognized by different sequence analyzer programs. Sequence Format includes accessory information, gene names, source organism, investigator name, references, and the actual sequence.
Sequence Formats (continued) • FASTA • GenBank Flat File format • PIR/CODATA format • EMBL sequence entry format • Intelligenetics sequence entry format • GCG (Genetics Computer Group) sequence entry format. • ASN.1 • XML
Databases • NCBI GenBank at the National Center of Biotechnology Information (NCBI), National Library of Medicine, Washington, DC • NBRF Protein Information Resource (PIR) database at the National Biomedical Research Foundation in Washington, DC
Databases (continued) • SwissProt The SwissProt protein sequence database at ISREC, Swiss Institute for Experimental Cancer Research. • EMBL European Molecular Biology Laboratory (EMBL) Outstation at Hixton, England • DDBJ DNA DataBank of Japan (DDBJ) at Mishima, Japan
Databases on Internet • NCBI http://www.ncbi.nlm.nih.gov • PIR http://www-nbrf.georgetown.edu/pirwww • SwissProt http://www.expasy.ch/cgi-bin/sprot-search-de • EMBL http://www.ebi.ac.uk/embl/index.html • DDBJ http://www.ddbj.nig.ac.jp/
NCBI • National resource for molecular biology information. • Maintains comprehensive databases for variety of Biotech related information. • Develops and manages access to a range of databases and softwares for scientific and medical communities.
NCBI : Integrated Databases • Literature Databases • Pubmed • PubMed Central • OMIM • PROW • BookShelf
NCBI : Integrated Databases (continued) • Nucleotide Databases • GenBank • EST Database • GSS Database • SNPs Database • RefSeq • STS Database
NCBI : Integrated Databases (continued) • Entrez Databases • Pubmed • Protein Sequence Database • Nucleotide Sequence Database • Taxonomy • OMIM
GenBank • GenBank is the NIH genetic sequence database. • Annotated collection of all publicly available DNA sequences. • GenBank is a part of an international collaboration of sequence databases along with EMBL and DDBJ.
GenBank DNA Sequence Format DNA sequence in GenBank is formatted into distinct attributes as following • Locus: locus name, sequence length, division, date • Definition: description of entry • Accession: unique accession number • Version: version of sequence • Keywords: keywords for cross referencing
GenBank DNA Sequence Format(continued) • Source: source organism of DNA • Organism: description of organism • References: authors, title, journal, Medline, etc • Features: information about sequence • Basecount: number of bases in sequence • Origin: sequence data begin following origin. • Genebank sample
NCBI : Tools Tools for Data Retrieval and submission • Text Term Searching • Sequence Similarity Searching • Taxonomy Searching • Sequence Submission
NCBI : ENTREZ • Entrez is a search and retrieval system that integrates information from databases at NCBI. • These databases include nucleotide sequences, protein sequences, macromolecular structures, whole genomes, and MEDLINE, PubMed. Etc. • Entrez
NCBI : BLAST BLAST: Basic Local Alignment Search Tool • It is a set of similarity search programs designed to explore available sequence databases. • It uses a heuristic algorithm which is able to detect relationships among sequences which share only isolated regions of similarity Q-BLAST: It is a queuing system to BLAST that allows users to retrieve results at their convenience and format their results.
NCBI : BLAST (continued) Access to BLAST service • Web-BLAST • Standalone BLAST • Network BLAST • BLAST URL API
NCBI : BLAST (continued) BLAST Programs • Blastp : Compares amino acid sequence against protein sequence Database • Blastn : Compares nucleotide sequence against nucleotide sequence Database • Blastx :Compares nucleotide query sequence against protein sequence Database • Tblastn : Compares protein query sequence against nucleotide sequence Database BLAST
NBRF :PIR Protein Information Resource 3 Major Databases: • PSD (Protein Sequence Database) • iProClass • PIR-NREF (Nonredundant REFerence protein database)
PIR: PSD • The PIR, in collaboration with MIPS and JIPID, produces and distributes the PIR-International Protein Sequence Database (PSD) . • Comprehensive and expertly annotated protein sequence database. • The primary sources of PSD data are sequences from GenBank/EMBL/DDBJ translations, published literature, and direct submission to PIR-International.
PIR: PSD (continued) • The PIR-PSD data is available in XML format and NBRF, PIR/CODATA formats. The sequence file is available in FASTA format. • Also available at PIR UNIX FTP server. Address: ftp://ftp.pir.georgetown.edu/pir_databases/psd/
CODATA format • CODATA format has approximately the same information as a GenBank or EMBL sequence file, but is slightly differently formatted and has different field names. • Also called PIR format, used by NBRF. CODATA Sample
PIR: iProClass • The iProClass database provides comprehensive descriptions of all proteins and serves as a framework for data integration in a distributed networking environment. • Very user-friendly description.
PIR: NREF (Non-redundant REFerence protein database) • Comprehensive: Containing all sequences from PIR-PSD, Swiss-Prot, TrEMBL, RefSeq, GenPept, and updated bi-weekly. • Non-Redundant: Clustered by sequence identity and taxonomy at the species level. • Source Attribution: Containing protein IDs and names from associated databases (with hypertext links), in addition to protein sequence, taxonomy, and bibliography. The current version (July 2002) consists of more than 809,000 non-redundant PIR-PSD, SwissProt and TrEMBL proteins organized with more than 36,200 PIR superfamilies, 145,340 families, and links to over 50 molecular biology databases.
Swiss-Prot • Swiss-Prot is a protein knowledgebase established in 1986. • Maintained collaboratively, by the Department of Medical Biochemistry of the University of Geneva (now the Swiss Institute of Bioinformatics) and the EMBL Data Library. Swiss-Prot Sequence Entry Example
Sequence Format Conversion READSEQ: Sequence Format Conversion program. http://bimas.dcrt.nih.gov/molbio/readseq/ Can convert to/from: • ASN.1 • FASTA • CODATA • GCG • EMBL format • GenBank format and many other formats
References • http://www.ncbi.nlm.nih.gov • http://www-nbrf.georgetown.edu/pirwww • http://www.expasy.ch/cgi-bin/sprot-search-de • http://www.ebi.ac.uk/embl/index.html • http://www.ddbj.nig.ac.jp/
Thank You Presented by:Hemal Patel &Jeetal Shah