NAME

Bio::AlignIO::stockholm - stockholm sequence input/output stream

SYNOPSIS

  # Do not use this module directly.  Use it via the L<Bio::AlignIO> class.

  use Bio::AlignIO;
  use strict;

  my $in = Bio::AlignIO->new(-format => 'stockholm',
                             -file   => 't/data/testaln.stockholm');
  while( my $aln = $in->next_aln ) {

  }

DESCRIPTION

This object can transform Bio::Align::AlignI objects to and from stockholm flat file databases. This has been completely refactored from the original stockholm parser to handle annotation data and now includes a write_aln() method for (almost) complete stockholm format output.

Stockholm alignment records normally contain additional sequence-based and alignment-based annotation

  GF Lines (alignment feature/annotation):
  #=GF <featurename> <Generic per-file annotation, free text>
  Placed above the alignment
  
  GC Lines (Alignment consensus)
  #=GC <featurename> <Generic per-column annotation, exactly 1
       character per column>
  Placed below the alignment

  GS Lines (Sequence annotations)
  #=GS <seqname> <featurename> <Generic per-sequence annotation, free
       text>

  GR Lines (Sequence meta data)
  #=GR <seqname> <featurename> <Generic per-sequence AND per-column
       mark up, exactly 1 character per column>

Currently, sequence annotations (those designated with GS tags) are parsed only for accession numbers and descriptions. It is intended that full parsing will be added at some point in the near future along with a builder option for optionally parsing alignment annotation and meta data.

The following methods/tags are currently used for storing and writing the alignment annotation data.

    Tag        SimpleAlign
                 Method  
    ----------------------------------------------------------------------
     AC        accession  
     ID        id  
     DE        description
    ----------------------------------------------------------------------
    
    Tag        Bio::Annotation   TagName                    Parameters
               Class
    ----------------------------------------------------------------------
     AU        SimpleValue       record_authors             value
     SE        SimpleValue       seed_source                value
     GA        SimpleValue       gathering_threshold        value
     NC        SimpleValue       noise_cutoff               value
     TC        SimpleValue       trusted_cutoff             value
     TP        SimpleValue       entry_type                 value
     SQ        SimpleValue       num_sequences              value
     PI        SimpleValue       previous_ids               value
     DC        Comment           database_comment           comment
     CC        Comment           alignment_comment          comment
     DR        DBLink            aln_dblink                 database
                                                            primary_id
                                                            comment
     AM        SimpleValue       build_method               value
     NE        SimpleValue       pfam_family_accession      value
     NL        SimpleValue       sequence_start_stop        value
     SS        SimpleValue       sec_structure_source       value
     BM        SimpleValue       build_model                value
     RN        Reference         reference                  *
     RC        Reference         reference                  comment
     RM        Reference         reference                  pubmed
     RT        Reference         reference                  title
     RA        Reference         reference                  authors
     RL        Reference         reference                  location
    ----------------------------------------------------------------------
  * RN is generated based on the number of Bio::Annotation::Reference objects

FEEDBACK

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 the web:

  http://bugzilla.open-bio.org/

AUTHORS - Chris Fields, Peter Schattner

Email: cjfields-at-uiuc-dot-edu, schattner@alum.mit.edu

CONTRIBUTORS

Andreas Kahari, ak-at-ebi.ac.uk Jason Stajich, jason-at-bioperl.org

APPENDIX

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

next_aln

 Title   : next_aln
 Usage   : $aln = $stream->next_aln()
 Function: returns the next alignment in the stream.
 Returns : L<Bio::Align::AlignI> object
 Args    : NONE

write_aln

 Title   : write_aln
 Usage   : $stream->write_aln(@aln)
 Function: writes the $aln object into the stream in stockholm format
 Returns : 1 for success and 0 for error
 Args    : L<Bio::Align::AlignI> object