Ewan Birney


Bio::DB::NCBIHelper - A collection of routines useful for queries to NCBI databases.


 Do not use this module directly.
 # get a Bio::DB::NCBIHelper object somehow
 my $seqio = $db->get_Stream_by_acc(['MUSIGHBA1']);
 foreach my $seq ( $seqio->next_seq ) {
  # process seq


Provides a single place to setup some common methods for querying NCBI web databases. This module just centralizes the methods for constructing a URL for querying NCBI GenBank and NCBI GenPept and the common HTML stripping done in postprocess_data().

The NCBI query URLs used are http://www.ncbi.nlm.nih.gov as the base URL, /cgi-bin/Entrez/qserver.cgi as the query interface for batch mode, and /entrez/utils/qmap.cgi for single-query mode.


Mailing Lists

User feedback is an integral part of the evolution of this and other Bioperl modules. Send your comments and suggestions preferably to one of the Bioperl mailing lists. Your participation is much appreciated.

  bioperl-l@bioperl.org              - General discussion
  http://bioperl.org/MailList.shtml  - About the mailing lists

Reporting Bugs

Report bugs to the Bioperl bug tracking system to help us keep track the bugs and their resolution. Bug reports can be submitted via email or the web:


AUTHOR - Jason Stajich

Email jason@bioperl.org


The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _


 Title   : get_params
 Usage   : my %params = $self->get_params($mode)
 Function: Returns key,value pairs to be passed to NCBI database
           for either 'batch' or 'single' sequence retrieval method
 Returns : a key,value pair hash
 Args    : 'single' or 'batch' mode for retrieval


 Title   : default_format
 Usage   : my $format = $self->default_format
 Function: Returns default sequence format for this module
 Returns : string
 Args    : none


 Title   : get_request
 Usage   : my $url = $self->get_request
 Function: HTTP::Request
 Returns : 
 Args    : %qualifiers = a hash of qualifiers (ids, format, etc)


  Title   : get_Stream_by_batch
  Usage   : $seq = $db->get_Stream_by_batch($ref);
  Function: Retrieves Seq objects from Entrez 'en masse', rather than one
            at a time.  For large numbers of sequences, this is far superior
            than get_Stream_by_[id/acc]().
  Example :
  Returns : a Bio::SeqIO stream object
  Args    : $ref : either an array reference, a filename, or a filehandle
            from which to get the list of unique ids/accession numbers.


 Title   : postprocess_data
 Usage   : $self->postprocess_data ( 'type' => 'string',
                                     'location' => \$datastr);
 Function: process downloaded data before loading into a Bio::SeqIO
 Returns : void
 Args    : hash with two keys - 'type' can be 'string' or 'file'
                              - 'location' either file location or string 
                                           reference containing data


 Title   : request_format
 Usage   : my ($req_format, $ioformat) = $self->request_format;
 Function: Get/Set sequence format retrieval. The get-form will normally not
           be used outside of this and derived modules.
 Returns : Array of two strings, the first representing the format for
           retrieval, and the second specifying the corresponding SeqIO format.
 Args    : $format = sequence format


 Title   : get_Seq_by_version
 Usage   : $seq = $db->get_Seq_by_version('X77802.1');
 Function: Gets a Bio::Seq object by sequence version
 Returns : A Bio::Seq object
 Args    : accession.version (as a string)
 Throws  : "acc.version does not exist" exception


  Title   : get_Stream_by_version
  Usage   : 
  Function: DO NOT USE. HACK.
            Reuses the method defined by the interface file to retrieve
            a HTML table with all GIs (versions) for a accession number.
  Returns : a HTTP::Request object
  Args    : $ref : a reference to an array of accession.version strings for
                   the desired sequence entries

Bio::DB::WebDBSeqI methods

Overriding WebDBSeqI method to help newbies to retrieve sequences


  Title   : get_Stream_by_acc
  Usage   : $seq = $db->get_Seq_by_acc([$acc1, $acc2]);
  Function: Gets a series of Seq objects by accession numbers
  Returns : a Bio::SeqIO stream object
  Args    : $ref : a reference to an array of accession numbers for
                   the desired sequence entries
  Note    : For GenBank, this just calls the same code for get_Stream_by_id()


  Title   : _check_id
  Usage   : 
  Returns : A Bio::DB::RefSeq reference or throws
  Args    : $id(s), $string