Provided by: libbio-perl-perl_1.7.8-1_all
NAME
Bio::Tools::AmpliconSearch - Find amplicons in a template using degenerate PCR primers
SYNOPSIS
use Bio::PrimarySeq; use Bio::Tools::AmpliconSearch; my $template = Bio::PrimarySeq->new( -seq => 'aaaaaCCCCaaaaaaaaaaTTTTTTaaaaaCCACaaaaaTTTTTTaaaaaaaaaa', ); my $fwd_primer = Bio::PrimarySeq->new( -seq => 'CCNC', ); my $rev_primer = Bio::PrimarySeq->new( -seq => 'AAAAA', ); my $search = Bio::Tools::AmpliconSearch->new( -template => $template, -fwd_primer => $fwd_primer, -rev_primer => $rev_primer, ); while (my $amplicon = $search->next_amplicon) { print "Found amplicon at position ".$amplicon->start.'..'.$amplicon->end.":\n"; print $amplicon->seq->seq."\n\n"; } # Now change the template (but you could change the primers instead) and look # for amplicons again $template = Bio::PrimarySeq->new( -seq => 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa', ); $search->template($template); while (my $amplicon = $search->next_amplicon) { print "Found amplicon at position ".$amplicon->start.'..'.$amplicon->end.":\n"; print $amplicon->seq->seq."\n\n"; }
DESCRIPTION
Perform an in silico PCR reaction, i.e. search for amplicons in a given template sequence using the specified degenerate primer. The template sequence is a sequence object, e.g. Bio::Seq, and the primers can be a sequence or a Bio::SeqFeature::Primer object and contain ambiguous residues as defined in the IUPAC conventions. The primer sequences are converted into regular expressions using Bio::Tools::IUPAC and the matching regions of the template sequence, i.e. the amplicons, are returned as Bio::Seq::PrimedSeq objects. AmpliconSearch will look for amplicons on both strands (forward and reverse- complement) of the specified template sequence. If the reverse primer is not provided, an amplicon will be returned and span a match of the forward primer to the end of the template. Similarly, when no forward primer is given, match from the beginning of the template sequence. When several amplicons overlap, only the shortest one to more accurately represent the biases of PCR. Future improvements may include modelling the effects of the number of PCR cycles or temperature on the PCR products.
TODO
Future improvements may include: • Allowing a small number of primer mismatches • Reporting all amplicons, including overlapping ones • Putting a limit on the length of amplicons, in accordance with the processivity of the polymerase used
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: https://github.com/bioperl/bioperl-live/issues
AUTHOR
Florent Angly <florent.angly@gmail.com>
APPENDIX
The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _ new Title : new Usage : my $search = Bio::Tools::AmpliconSearch->new( ); Function : Initialize an amplicon search Args : -template Sequence object for the template sequence. This object will be converted to Bio::Seq if needed in since features (amplicons and primers) will be added to this object. -fwd_primer A sequence object representing the forward primer -rev_primer A sequence object representing the reverse primer -primer_file Read primers from a sequence file. It replaces -fwd_primer and -rev_primer (optional) -attach_primers Whether or not to attach primers to Amplicon objects. Default: 0 (off) Returns : A Bio::Tools::AmpliconSearch object template Title : template Usage : my $template = $search->template; Function : Get/set the template sequence. Setting a new template resets any search in progress. Args : Optional Bio::Seq object Returns : A Bio::Seq object fwd_primer Title : fwd_primer Usage : my $primer = $search->fwd_primer; Function : Get/set the forward primer. Setting a new forward primer resets any search in progress. Args : Optional sequence object or primer object or '' to match beginning of sequence. Returns : A sequence object or primer object or undef rev_primer Title : rev_primer Usage : my $primer = $search->rev_primer; Function : Get/set the reverse primer. Setting a new reverse primer resets any search in progress. Args : Optional sequence object or primer object or '' to match end of sequence. Returns : A sequence object or primer object or undef primer_file Title : primer_file Usage : my ($fwd, $rev) = $search->primer_file; Function : Get/set a sequence file to read the primer from. The first sequence must be the forward primer, and the second is the optional reverse primer. After reading the file, the primers are set using fwd_primer() and rev_primer() and returned. Args : Sequence file Returns : Array containing forward and reverse primers as sequence objects. attach_primers Title : attach_primers Usage : my $attached = $search->attach_primers; Function : Get/set whether or not to attach primer objects to the amplicon objects. Args : Optional integer (1 for yes, 0 for no) Returns : Integer (1 for yes, 0 for no) next_amplicon Title : next_amplicon Usage : my $amplicon = $search->next_amplicon; Function : Get the next amplicon Args : None Returns : A Bio::SeqFeature::Amplicon object annotate_template Title : annotate_template Usage : my $template = $search->annotate_template; Function : Search for all amplicons and attach them to the template. This is equivalent to running: while (my $amplicon = $self->next_amplicon) { # do something } my $annotated = $self->template; Args : None Returns : A Bio::Seq object with attached Bio::SeqFeature::Amplicons (and Bio::SeqFeature::Primers if you set -attach_primers to 1).