EMBL format

Figure 4.3. EMBL format for nucleotide sequence of chicken egg-white lysozyme.

EMBL-DB= Library [EMBL group SSEQUENCE-LIBS format EMBL FORMAT searchName . dat ... 

The EMBL library object, (Figure 1.8), defines the EMBL library as being part of the sequence library group, with the format being described in the EMBL FORMAT object (Figure 1.9) and the files which make up the EMBL database being all those files with the extension dat in the EMBL flat file directory. 

The EMBL FORMAT object contains a list of fields which make up the database. In our example EMBL database the library has 5 fields. 

EMBL-FORMAT= LibFormat [syntax EMBL SYNTAX contains DNASEQ DATA f ileType DAT-FILE SEQ FILE fields ... 

This database contains sequence exemplars of repetitive DNA from different eukaryotic species. Most entries are consensus sequences of large families and subfamilies of repeats, with smaller families represented by sequence examples. The entries include annotations and references and are released in EMBL format. Repbase Update [38M-0] is used by both CENSOR and RepeatMasker, which masks out these common repeats to speed up other analyses. Repbase Update is free to academic users. Commercial users need a license. 

This is fundamental to the progress of genomics (and many other areas) of science. Generating data in a common exchangeable format, with a common lexicon of terms [47] in a single non-redundant location is a major goal. A number of examples exist, such as the DNA and protein sequence data in GenBank, EMBL or SwissProt [48-50]. 

The DR lines link SWISS-PROT to other biomolecular databases. SWISS-PROT is currently linked to 29 different databases. The preceding example shows links to 19 different entries in 6 different databases. The cross references allow users to navigate to linked databases to retrieve part or all of the related information. The format of a DR line, except for cross references to PROSITE (Hofmann et al., 1999), Pfam (Bateman et al., 1999), and the EMBL nucleotide sequence databases (Stoesser et al., 1999), is the following ... 

The specific format for cross references to the EMBL nucleotide sequence database is ... 

There are four textboxes with corresponding data field selectors. After entering querystrings to textboxes and choosing data fields, select sequence formats (embl, fasta or genbank) and then click the Submit Query button to begin the search. 

Each SWISS-PROT entry consists of general information about the entry (e.g., entry name and date, accession number), Name and origin of the protein (e.g., protein name, EC number and biological origin), References, Comments (e.g., catalytic activity, cofactor, subuit structure, subcellular location and family class, etc.), Cross-reference (EMBL, PIR, PDB, Pfam, ProSite, ProDom, ProtoMap, etc.), Keywords, Features (e.g., active site, binding site, modification, secondary structures, etc.), and Sequence information (amino acid sequence in Swiss-Prot format, Chapter 4). 

SWISS-PROT (Hofmann et al., 1999) is a curated protein sequence database maintained by the Swiss Institute of Bioinfornmatics and is a collaborative partner of EMBL. The database consists of SWISS-PROT and TrEMBL, which consists of entries in SWISS-PROT-like format derived from the translation of all CDS in the... 

EMBL Nucleotide Sequence Database. SWISS-PROT consists of core sequence data with minimal redundancy, citation and extensive annotations including protein function, post-translational modifications, domain sites, protein structural information, diseases associated with protein deficiencies and variants. SWISS-PROT and TrEMBL are available at EBI site, http //www.ebi.ac.uk/swissprot/, and ExPASy site, http //www.expasy.ch/sprot/. From the SWISS-PROT and TrEMBL page of ExPASy site, click Full text search (under Access to SWISS-PROT and TrEMBL) to open the search page (Figure 11.3). Enter the keyword string (use Boolean expression if required), check SWISS-PROT box, and click the Submit button. Select the desired entry from the returned list to view the annotated sequence data in Swiss-Prot format. An output in the fasta format can be requested. Links to BLAST, feature table, some ExPASy proteomic tools (e.g., Compute pI/Mw, ProtParam, ProfileScan, ProtScale, PeptideMass, ScanProsite), and structure (SWISS-MODEL) are provided on the page. 

The first databases to appear were DNA sequence databases, namely those from the EMBL (Europe), NCBI (USA) and the DDBJ (Japan), known as EMBL [30], GENBANK [18] and DDBJ [1] respectively. These are DNA databases of sequences and their annotations. These databases continue as a collaborative effort, with the three databases sharing their information. So all three databases contain identical data, albeit in a different format. 

Nucleotide Sequence Database [26]) steps in. TrEMBL was created in 1996 and consists of computer-annotated entries in SWISS-PROT-like format. It is populated by protein sequences translated from the coding sequences (CDS) in EMBL and is a supplement to SWISS-PROT. In a way, it can be considered as a preliminary section of SWISS-PROT indeed, once the manual annotation is performed, the entries move on to SWISS-PROT. 

If it is necessary to upload sequence files, these can be compressed using either WinZip, or the UNIX gzip utility, which will significantly reduce the time taken to upload the data. Submitted files should each contain a single sequence in EMBL or FASTA format. It is preferable to use EMBL/Genbank format for uploaded sequences, because any genes annotated in the feature table will then be displayed by ACT. Should multiple sequences be present in an uploaded file, only the first will be used. 

A full release of GenBank occins on a bimonthly schedule with incremental (and nonincremental) daily updates available by anonymous FTP. The International Nucleotide Sequence Database Collaboration also exchanges new and updated records daily. Therefore, all sequences present in GenBank are also present in DDBJ and EMBL, as described in the introduction to this chapter. The three databases rely on a common data format for information described in the feature table documentation (see below). This represents the lingua franca for nucleotide sequence database annotations. Together, the nucleotide sequence databases have developed defined submission procedures (see Chapter 4), a series of guidelines for the content and format of all records. 

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