NAME
Bio::Tools::Run::TigrAssembler - Wrapper for local execution of TIGR Assembler v2
SYNOPSIS
use Bio::Tools::Run::TigrAssembler;
# Run TIGR Assembler using an input FASTA file
my $factory = Bio::Tools::Run::TigrAssembler->new( -minimum_overlap_length => 35 );
my $asm_obj = $factory->run($fasta_file, $qual_file);
# An assembly object is returned by default
for my $contig ($assembly->all_contigs) {
... do something ...
}
# Read some sequences
use Bio::SeqIO;
my $sio = Bio::SeqIO->new(-file => $fasta_file, -format => 'fasta');
my @seqs;
while (my $seq = $sio->next_seq()) {
push @seqs,$seq;
}
# Run TIGR Assembler with input sequence objects and return an assembly file
my $asm_file = 'results.tigr';
$factory->out_type($asm_file);
$factory->run(\@seqs);
# Use LIGR Assembler instead
my $ligr = Bio::Tools::Run::TigrAssembler->new(
-program_name => 'LIGR_Assembler',
-trimmed_seq => 1
);
$ligr->run(\@seqs);
DESCRIPTION
Wrapper module for the local execution of the DNA assembly program TIGR
Assembler v2.0. TIGR Assembler is open source software under The Artistic
License and available at: http://www.tigr.org/software/assembler/
This module runs TIGR Assembler by feeding it a FASTA file or sequence objects
and returning an assembly file or assembly and IO objects. When the input is
Bioperl object, sequences less than 39 bp long are filtered out since they are
not supported by TIGR Assembler.
If provided in the following way, TIGR Assembler will use additional
information present in the sequence descriptions for assembly:
>seq_name minimum_clone_length maximum_clone_length median_clone_length
clear_end5 clear_end3
or
>db|seq_name minimum_clone_length maximum_clone_length median_clone_length
clear_end5 clear_end3
e.g.
>GHIBF57F 500 3000 1750 33 587
This module also supports LIGR Assembler, a variant of TIGR Assembler:
http://sourceforge.net/projects/ligr-assembler/
FEEDBACK
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/wiki/Mailing_lists - About the mailing lists
Support
Please direct usage questions or support issues to the mailing list:
bioperl-l@bioperl.org
rather than to the module maintainer directly. Many experienced and reponsive experts will be able look at the problem and quickly address it. Please include a thorough description of the problem with code and data examples if at all possible.
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://redmine.open-bio.org/projects/bioperl/
AUTHOR - Florent E Angly
Email: florent-dot-angly-at-gmail-dot-com
APPENDIX
The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _
new
Title : new
Usage : $factory->new( -minimum_percent => 95,
-minimum_length => 50,
-include_singlets => 1 );
Function: Create a TIGR Assembler factory
Returns : A Bio::Tools::Run::TigrAssembler object
Args :
TIGR Assembler options available in this module:
minimum_percent / minimum_overlap_similarity: the minimum percent identity
that two DNA fragments must achieve over their entire region of overlap in
order to be considered as a possible assembly. Adjustments are made by the
program to take into account that the ends of sequences are lower quality
and doubled base calls are the most frequent sequencing error.
minimum_length / minimum_overlap_length: the minimum length two DNA fragments
must overlap to be considered as a possible assembly (warning: this option
is not strictly respected by TIGR Assembler...)
include_singlets: a flag which indicates that singletons (assemblies made up
of a single DNA fragment) should be included in the lassie output_file - the
default is to not include singletons.
max_err_32: the maximum number + 1 of alignment errors (mismatches or gaps)
allowed within any contiguous 32 base pairs in the overlap region between
two DNA fragments in the same assembly. This is meant to split apart splice
variants which have short splice differences and would not be disqualified
by the -p minimum_percent parameter.
consider_low_scores: a flag which causes even very LOW pairwise scores to be
considered - caution using this flag may cause longer run time and a worse
assembly.
maximum_end: the maximum length at the end of a DNA fragment that does not
match another overlapping DNA fragment (sometimes referred to as overhang)
that will not disqualify a DNA fragment from becoming part of an assembly.
ignore_tandem_32mers: a flag which causes tandem 32mers (a tandem 32mer is a
32mer which occurs more than once in at least one sequence read) to be
ignored (this is now the default behavior and this flag is for backward
compatibility)
use_tandem_32mers: a flag which causes tandem 32mers to be used for pairwise
comparison opposite of the -t flag which is now the default).
safe_merging_stop: a flag which causes merging to stop when only sequences
which appear to be repeats are left and these cannot be merged based on
clone length constraints.
not_random: a flag which indicates that the DNA fragments in the input_file
should not be treated as random genomic fragments for the purpose of
determining repeat regions.
resort_after: specifies how many sequences should be merged before resorting
the possible merges based on clone constraints.
LIGR Assembler has the same options as TIGR Assembler, and the following:
incl_bad_seq: keep all sequences including potential chimeras and splice variants
trimmed_seq: indicates that the sequences are trimmed. High quality scores will be
given on the whole sequence length instead of just in the middle)
out_type
Title : out_type
Usage : $factory->out_type('Bio::Assembly::ScaffoldI')
Function: Get/set the desired type of output
Returns : The type of results to return
Args : Desired type of results to return (optional):
'Bio::Assembly::IO' object
'Bio::Assembly::ScaffoldI' object (default)
The name of a file to save the results in
run
Title : run
Usage : $factory->run($fasta_file);
Function: Run TIGR Assembler
Returns : - a Bio::Assembly::ScaffoldI object, a Bio::Assembly::IO
object, a filename, or undef if all sequences were too small to
be usable
Returns : Assembly results (file, IO object or assembly object)
Args : - sequence input (FASTA file or sequence object arrayref)
- optional quality score input (QUAL file or quality score object
arrayref)
_run
Title : _run
Usage : $assembler->_run()
Function: Make a system call and run Newbler
Returns : An assembly file
Args : - FASTA file, SFF file and MID, or analysis dir and MID
- optional QUAL file
_remove_small_sequences
Title : _remove_small_sequences
Usage : $assembler->_remove_small_sequences(\@seqs, \@quals)
Function: Remove sequences below a threshold length
Returns : a new sequence object array reference
a new quality score object array reference
Args : sequence object array reference
quality score object array reference (optional)