SYNOPSIS
my $hsp = Bio::Search::HSP::GenericHSP->new( -algorithm => 'blastp',
-evalue => '1e-30',
);
$r_type = $hsp->algorithm;
$pvalue = $hsp->p();
$evalue = $hsp->evalue();
$frac_id = $hsp->frac_identical( ['query'|'hit'|'total'] );
$frac_cons = $hsp->frac_conserved( ['query'|'hit'|'total'] );
$gaps = $hsp->gaps( ['query'|'hit'|'total'] );
$qseq = $hsp->query_string;
$hseq = $hsp->hit_string;
$homo_string = $hsp->homology_string;
$len = $hsp->length( ['query'|'hit'|'total'] );
$len = $hsp->length( ['query'|'hit'|'total'] );
$rank = $hsp->rank;
# TODO: Describe how to configure a SearchIO stream so that it generates # GenericHSP objects.
DESCRIPTION
This implementation is ``Generic'', meaning it is is suitable for holding information about High Scoring pairs from most Search reports such as BLAST and FastA. Specialized objects can be derived from this.Unless you're writing a parser, you won't ever need to create a GenericHSP or any other HSPI-implementing object. If you use the SearchIO system, HSPI objects are created automatically from a SearchIO stream which returns Bio::Search::Result::ResultI objects and you get the HSPI objects via the ResultI API.
For documentation on what you can do with GenericHSP (and other HSPI objects), please see the API documentation in Bio::Search::HSP::HSPI.
FEEDBACK
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Support
Please direct usage questions or support issues to the mailing list: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 of the bugs and their resolution. Bug reports can be submitted via the web:
https://github.com/bioperl/bioperl-live/issues
AUTHOR - Jason Stajich and Steve Chervitz
Email jason-at-bioperl.org Email sac-at-bioperl.orgCONTRIBUTORS
Sendu Bala, [email protected]APPENDIX
The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _new
Title : new
Usage : my $obj = Bio::Search::HSP::GenericHSP->new();
Function: Builds a new Bio::Search::HSP::GenericHSP object
Returns : Bio::Search::HSP::GenericHSP
Args : -algorithm => algorithm used (BLASTP, TBLASTX, FASTX, etc)
-evalue => evalue
-pvalue => pvalue
-bits => bit value for HSP
-score => score value for HSP (typically z-score but depends on
analysis)
-hsp_length=> Length of the HSP (including gaps)
-identical => # of residues that that matched identically
-percent_identity => (optional) percent identity
-conserved => # of residues that matched conservatively
(only protein comparisions;
conserved == identical in nucleotide comparisons)
-hsp_gaps => # of gaps in the HSP
-query_gaps => # of gaps in the query in the alignment
-hit_gaps => # of gaps in the subject in the alignment
-query_name => HSP Query sequence name (if available)
-query_start => HSP Query start (in original query sequence coords)
-query_end => HSP Query end (in original query sequence coords)
-query_length=> total length of the query sequence
-query_seq => query sequence portion of the HSP
-query_desc => textual description of the query
-hit_name => HSP Hit sequence name (if available)
-hit_start => HSP Hit start (in original hit sequence coords)
-hit_end => HSP Hit end (in original hit sequence coords)
-hit_length => total length of the hit sequence
-hit_seq => hit sequence portion of the HSP
-hit_desc => textual description of the hit
-homology_seq=> homology sequence for the HSP
-hit_frame => hit frame (only if hit is translated protein)
-query_frame => query frame (only if query is translated protein)
-rank => HSP rank
-links => HSP links information (WU-BLAST only)
-hsp_group => HSP Group informat (WU-BLAST only)
-gap_symbol => symbol representing a gap (default = '-')
-hit_features=> string of features found in or near HSP hit
region (reported in some BLAST text output,
v. 2.2.13 and up)
-stranded => If the algorithm isn't known (i.e. defaults to
'generic'), setting this will indicate start/end
coordinates are to be used to determine the strand
for 'query', 'subject', 'hit', 'both', or 'none'
(default = 'none')
Bio::Search::HSP::HSPI methods
Implementation of Bio::Search::HSP::HSPI methods followalgorithm
Title : algorithm Usage : my $r_type = $hsp->algorithm Function: Obtain the name of the algorithm used to obtain the HSP Returns : string (e.g., BLASTP) Args : [optional] scalar string to set value
pvalue
Title : pvalue
Usage : my $pvalue = $hsp->pvalue();
Function: Returns the P-value for this HSP or undef
Returns : float or exponential (2e-10)
P-value is not defined with NCBI Blast2 reports.
Args : [optional] numeric to set value
evalue
Title : evalue Usage : my $evalue = $hsp->evalue(); Function: Returns the e-value for this HSP Returns : float or exponential (2e-10) Args : [optional] numeric to set value
frac_identical
Title : frac_identical
Usage : my $frac_id = $hsp->frac_identical( ['query'|'hit'|'total'] );
Function: Returns the fraction of identitical positions for this HSP
Returns : Float in range 0.0 -> 1.0
Args : arg 1: 'query' = num identical / length of query seq (without gaps)
'hit' = num identical / length of hit seq (without gaps)
synonyms: 'sbjct', 'subject'
'total' = num identical / length of alignment (with gaps)
synonyms: 'hsp'
default = 'total'
arg 2: [optional] frac identical value to set for the type requested
Note : for translated sequences, this adjusts the length accordingly
frac_conserved
Title : frac_conserved
Usage : my $frac_cons = $hsp->frac_conserved( ['query'|'hit'|'total'] );
Function : Returns the fraction of conserved positions for this HSP.
This is the fraction of symbols in the alignment with a
positive score.
Returns : Float in range 0.0 -> 1.0
Args : arg 1: 'query' = num conserved / length of query seq (without gaps)
'hit' = num conserved / length of hit seq (without gaps)
synonyms: 'sbjct', 'subject'
'total' = num conserved / length of alignment (with gaps)
synonyms: 'hsp'
default = 'total'
arg 2: [optional] frac conserved value to set for the type requested
gaps
Title : gaps
Usage : my $gaps = $hsp->gaps( ['query'|'hit'|'total'] );
Function : Get the number of gap characters in the query, hit, or total alignment.
Returns : Integer, number of gaps or 0 if none
Args : arg 1: 'query' = num gap characters in query seq
'hit' = num gap characters in hit seq; synonyms: 'sbjct', 'subject'
'total' = num gap characters in whole alignment; synonyms: 'hsp'
default = 'total'
arg 2: [optional] integer gap value to set for the type requested
query_string
Title : query_string Usage : my $qseq = $hsp->query_string; Function: Retrieves the query sequence of this HSP as a string Returns : string Args : [optional] string to set for query sequence
hit_string
Title : hit_string Usage : my $hseq = $hsp->hit_string; Function: Retrieves the hit sequence of this HSP as a string Returns : string Args : [optional] string to set for hit sequence
homology_string
Title : homology_string
Usage : my $homo_string = $hsp->homology_string;
Function: Retrieves the homology sequence for this HSP as a string.
: The homology sequence is the string of symbols in between the
: query and hit sequences in the alignment indicating the degree
: of conservation (e.g., identical, similar, not similar).
Returns : string
Args : [optional] string to set for homology sequence
consensus_string
Title : consensus_string
Usage : my $cs_string = $hsp->consensus_string;
Function: Retrieves the consensus structure line for this HSP as a string (HMMER).
: If the model had any consensus structure or reference line annotation
: that it inherited from a multiple alignment (#=GC SS cons,
: #=GC RF annotation in Stockholm files), that information is shown
: as CS or RF annotation line.
Returns : string
Args : [optional] string to set for consensus structure
posterior_string
Title : posterior_string
Usage : my $pp_string = $hsp->posterior_string;
Function: Retrieves the posterior probability line for this HSP as a string (HMMer3).
: The posterior probability is the string of symbols at the bottom
: of the alignment indicating the expected accuracy of each aligned residue.
: A 0 means 0-5%, 1 means 5-15%, and so on; 9 means 85-95%,
: and a * means 95-100% posterior probability.
Returns : string
Args : [optional] string to set for posterior probability
length
Title : length
Usage : my $len = $hsp->length( ['query'|'hit'|'total'] );
Function : Returns the length of the query or hit in the alignment
(without gaps)
or the aggregate length of the HSP (including gaps;
this may be greater than either hit or query )
Returns : integer
Args : arg 1: 'query' = length of query seq (without gaps)
'hit' = length of hit seq (without gaps) (synonyms: sbjct, subject)
'total' = length of alignment (with gaps)
default = 'total'
arg 2: [optional] integer length value to set for specific type
hsp_length
Title : hsp_length
Usage : my $len = $hsp->hsp_length()
Function: shortcut length('hsp')
Returns : floating point between 0 and 100
Args : none
percent_identity
Title : percent_identity Usage : my $percentid = $hsp->percent_identity() Function: Returns the calculated percent identity for an HSP Returns : floating point between 0 and 100 Args : none
frame
Title : frame
Usage : my ($qframe, $hframe) = $hsp->frame('list',$queryframe,$subjectframe)
Function: Set the Frame for both query and subject and insure that
they agree.
This overrides the frame() method implementation in
FeaturePair.
Returns : array of query and subject frame if return type wants an array
or query frame if defined or subject frame if not defined
Args : 'hit' or 'subject' or 'sbjct' to retrieve the frame of the subject (default)
'query' to retrieve the query frame
'list' or 'array' to retrieve both query and hit frames together
Note : Frames are stored in the GFF way (0-2) not 1-3
as they are in BLAST (negative frames are deduced by checking
the strand of the query or hit)
get_aln
Title : get_aln Usage : my $aln = $hsp->gel_aln Function: Returns a L<Bio::SimpleAlign> object representing the HSP alignment Returns : L<Bio::SimpleAlign> Args : none
num_conserved
Title : num_conserved Usage : $obj->num_conserved($newval) Function: returns the number of conserved residues in the alignment Returns : integer Args : integer (optional)
num_identical
Title : num_identical Usage : $obj->num_identical($newval) Function: returns the number of identical residues in the alignment Returns : integer Args : integer (optional)
rank
Usage : $hsp->rank( [string] );
Purpose : Get the rank of the HSP within a given Blast hit.
Example : $rank = $hsp->rank;
Returns : Integer (1..n) corresponding to the order in which the HSP
appears in the BLAST report.
seq_inds
Title : seq_inds
Purpose : Get a list of residue positions (indices) for all identical
: or conserved residues in the query or sbjct sequence.
Example : @s_ind = $hsp->seq_inds('query', 'identical');
: @h_ind = $hsp->seq_inds('hit', 'conserved');
: @h_ind = $hsp->seq_inds('hit', 'conserved-not-identical');
: @h_ind = $hsp->seq_inds('hit', 'conserved', 1);
Returns : List of integers
: May include ranges if collapse is true.
Argument : seq_type = 'query' or 'hit' or 'sbjct' (default = query)
: ('sbjct' is synonymous with 'hit')
: class = 'identical' - identical positions
: 'conserved' - conserved positions
: 'nomatch' - mismatched residue or gap positions
: 'mismatch' - mismatched residue positions (no gaps)
: 'gap' - gap positions only
: 'frameshift'- frameshift positions only
: 'conserved-not-identical' - conserved positions w/o
: identical residues
: The name can be shortened to 'id' or 'cons' unless
: the name is . The default value is
: 'identical'
:
: collapse = boolean, if true, consecutive positions are merged
: using a range notation, e.g., "1 2 3 4 5 7 9 10 11"
: collapses to "1-5 7 9-11". This is useful for
: consolidating long lists. Default = no collapse.
:
Throws : n/a.
Comments : For HSPs partially or completely derived from translated sequences
: (TBLASTN, BLASTX, TBLASTX, or similar), some positional data
: cannot easily be attributed to a single position (i.e. the
: positional data is ambiguous). In these cases all three codon
: positions are reported. Under these conditions you can check
: ambiguous_seq_inds() to determine whether the query, subject,
: or both are ambiguous.
:
See Also : L<Bio::Search::SearchUtils::collapse_nums()|Bio::Search::SearchUtils>,
L<Bio::Search::Hit::HitI::seq_inds()|Bio::Search::Hit::HitI>
ambiguous_seq_inds
Title : ambiguous_seq_inds
Purpose : returns a string denoting whether sequence indices for query,
: subject, or both are ambiguous
Returns : String; 'query', 'subject', 'query/subject', or empty string ''
Argument : none
Comments : For HSPs partially or completely derived from translated sequences
: (TBLASTN, BLASTX, TBLASTX, or similar), some positional data
: cannot easily be attributed to a single position (i.e. the
: positional data is ambiguous). In these cases all three codon
: positions are reported when using seq_inds(). Under these
: conditions you can check ambiguous_seq_inds() to determine whether
: the query, subject, or both are ambiguous.
See Also : L<Bio::Search::Hit::HSPI::seq_inds()>
Inherited from Bio::SeqFeature::SimilarityPair
These methods come from Bio::SeqFeature::SimilarityPairquery
Title : query Usage : my $query = $hsp->query Function: Returns a SeqFeature representing the query in the HSP Returns : L<Bio::SeqFeature::Similarity> Args : [optional] new value to set
hit
Title : hit Usage : my $hit = $hsp->hit Function: Returns a SeqFeature representing the hit in the HSP Returns : L<Bio::SeqFeature::Similarity> Args : [optional] new value to set
significance
Title : significance
Usage : $evalue = $obj->significance();
$obj->significance($evalue);
Function: Get/Set the significance value
Returns : numeric
Args : [optional] new value to set
strand
Title : strand
Usage : $hsp->strand('query')
Function: Retrieves the strand for the HSP component requested
Returns : +1 or -1
Args : 'hit' or 'subject' or 'sbjct' to retrieve the strand of the subject,
'query' to retrieve the query strand (default)
score
Title : score
Usage : $score = $obj->score();
$obj->score($value);
Function: Get/Set the score value
Returns : numeric
Args : [optional] new value to set
bits
Title : bits
Usage : $bits = $obj->bits();
$obj->bits($value);
Function: Get/Set the bits value
Returns : numeric
Args : [optional] new value to set
Private methods
_calculate_seq_positions
Title : _calculate_seq_positions Usage : $self->_calculate_seq_positions Function: Internal function Returns : Args :
n
See documentation in Bio::Search::HSP::HSPI::n()range
See documentation in Bio::Search::HSP::HSPI::range()links
Title : links
Usage : $obj->links($newval)
Function: Get/Set the Links value (from WU-BLAST)
Indicates the placement of the alignment in the group of HSPs
Returns : Value of links
Args : On set, new value (a scalar or undef, optional)
hsp_group
Title : hsp_group
Usage : $obj->hsp_group($newval)
Function: Get/Set the Group value (from WU-BLAST)
Indicates a grouping of HSPs
Returns : Value of group
Args : On set, new value (a scalar or undef, optional)
hit_features
Title : hit_features
Usage : $obj->hit_features($newval)
Function: Get/Set the HSP hit feature string (from some BLAST 2.2.13 text
output), which is a string of overlapping or nearby features in HSP
hit
Returns : Value of hit features, if present
Args : On set, new value (a scalar or undef, optional)
Brief introduction on cigar string
NOTE: the concept is originally from EnsEMBL docs at http://may2005.archive.ensembl.org/Docs/wiki/html/EnsemblDocs/CigarFormat.html Please append to these docs if you have a better definition.Sequence alignment hits can be stored in a database as ungapped alignments. This imposes 2 major constraints on alignments:
a) alignments for a single hit record require multiple rows in the database, and b) it is not possible to accurately retrieve the exact original alignment.
Alternatively, sequence alignments can be stored as gapped alignments using the CIGAR line format (where CIGAR stands for Concise Idiosyncratic Gapped Alignment Report).
In the cigar line format alignments are stored as follows:
M: Match D: Deletion I: Insertion
An example of an alignment for a hypthetical protein match is shown below:
Query: 42 PGPAGLP----GSVGLQGPRGLRGPLP-GPLGPPL...
PG P G GP R PLGP
Sbjct: 1672 PGTP*TPLVPLGPWVPLGPSSPR---LPSGPLGPTD...
protein_align_feature table as the following cigar line:
7M4D12M2I2MD7M
cigar_string
Name: cigar_string Usage: $cigar_string = $hsp->cigar_string Function: Generate and return cigar string for this HSP alignment Args: No input needed Return: a cigar string
generate_cigar_string
Name: generate_cigar_string Usage: my $cigar_string = Bio::Search::HSP::GenericHSP::generate_cigar_string ($qstr, $hstr); Function: generate cigar string from a simple sequence of alignment. Args: the string of query and subject Return: cigar string