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Bio::CodonUsage::Table

NAME

Bio::CodonUsage::Table - for access to the Codon usage Database at http://www.kazusa.or.jp/codon.

SYNOPSIS

use Bio::CodonUsage::Table;
use Bio::DB::CUTG;
use Bio::CodonUsage::IO;
use Bio::Tools::SeqStats;
# Get a codon usage table from web database
my $cdtable = Bio::DB::CUTG->new(-sp => 'Mus musculus',
-gc => 1);
# Or from local file
my $io = Bio::CodonUsage::IO->new(-file => "file");
my $cdtable = $io->next_data();
# Or create your own from a Bio::PrimarySeq compliant object,
# $codonstats is a ref to a hash of codon name /count key-value pairs
my $codonstats = Bio::Tools::SeqStats->count_codons($Seq_objct);
# '-data' must be specified, '-species' and 'genetic_code' are optional
my $CUT = Bio::CodonUsage::Table->new(-data => $codonstats,
-species => 'Hsapiens_kinase');
print "leu frequency is ", $cdtable->aa_frequency('LEU'), "\n";
print "freq of ATG is ", $cdtable->codon_rel_frequency('ttc'), "\n";
print "abs freq of ATG is ", $cdtable->codon_abs_frequency('ATG'), "\n";
print "number of ATG codons is ", $cdtable->codon_count('ATG'), "\n";
print "GC content at position 1 is ", $cdtable->get_coding_gc('1'), "\n";
print "total CDSs for Mus musculus is ", $cdtable->cds_count(), "\n";

DESCRIPTION

This class provides methods for accessing codon usage table data.

All of the methods at present are simple look-ups of the table or are derived from simple calculations from the table. Future methods could include measuring the codon usage of a sequence , for example, or provide methods for examining codon usage in alignments.

SEE ALSO

Bio::Tools::CodonTable, Bio::WebAgent, Bio::CodonUsage::IO, Bio::DB::CUTG

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 AT bioperl DOT 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 AT bioperl DOT 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

AUTHORS

Richard Adams, Richard DOT Adams AT ed DOT ac DOT uk

APPENDIX

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

new
Title : new
Usage : my $cut = Bio::CodonUsage::Table->new(-data => $cut_hash_ref,
-species => 'H.sapiens_kinase'
-genetic_code =>1);
Returns : a reference to a new Bio::CodonUsage::Table object
Args : none or a reference to a hash of codon counts. This constructor is
designed to be compatible with the output of
Bio::Tools::SeqUtils::count_codons()
Species and genetic code parameters can be entered here or via the
species() and genetic_code() methods separately.

all_aa_frequencies
Title : all_aa_frequencies
Usage : my $freq = $cdtable->all_aa_frequencies();
Returns : a reference to a hash where each key is an amino acid
and each value is its frequency in all proteins in that
species.
Args : none

codon_abs_frequency
Title : codon_abs_frequency
Usage : my $freq = $cdtable->codon_abs_frequency('CTG');
Purpose : To return the frequency of that codon as a percentage
of all codons in the organism.
Returns : a percentage frequency
Args : a non-ambiguous codon string

codon_rel_frequency
Title : codon_rel_frequency
Usage : my $freq = $cdtable->codon_rel_frequency('CTG');
Purpose : To return the frequency of that codon as a percentage
of codons coding for the same amino acid. E.g., ATG and TGG
would return 100 as those codons are unique.
Returns : a percentage frequency
Args : a non-ambiguous codon string

probable_codons
Title : probable_codons
Usage : my $prob_codons = $cd_table->probable_codons(10);
Purpose : to obtain a list of codons for the amino acid above a given
threshold % relative frequency
Returns : A reference to a hash where keys are 1 letter amino acid codes
and values are references to arrays of codons whose frequency
is above the threshold.
Arguments: a minimum threshold frequency

most_common_codons
Title : most_common_codons
Usage : my $common_codons = $cd_table->most_common_codons();
Purpose : To obtain the most common codon for a given amino acid
Returns : A reference to a hash where keys are 1 letter amino acid codes
and the values are the single most common codons for those amino acids
Arguments: None

codon_count
Title : codon_count
Usage : my $count = $cdtable->codon_count('CTG');
Purpose : To obtain the absolute number of the codons in the
organism.
Returns : an integer
Args : a non-ambiguous codon string

get_coding_gc
Title : get_coding_gc
Usage : my $count = $cdtable->get_coding_gc(1);
Purpose : To return the percentage GC composition for the organism at
codon positions 1,2 or 3, or an average for all coding sequence
('all').
Returns : a number (%-age GC content) or 0 if these fields are undefined
Args : 1,2,3 or 'all'.

set_coding_gc
Title : set_coding_gc
Usage : my $count = $cdtable->set_coding_gc(-1=>55.78);
Purpose : To set the percentage GC composition for the organism at
codon positions 1,2 or 3, or an average for all coding sequence
('all').
Returns : void
Args : a hash where the key must be 1,2,3 or 'all' and the value the %age GC
at that codon position..

species
Title : species
Usage : my $sp = $cut->species();
Purpose : Get/setter for species name of codon table
Returns : Void or species name string
Args : None or species name string

genetic_code
Title : genetic_code
Usage : my $sp = $cut->genetic_code();
Purpose : Get/setter for genetic_code name of codon table
Returns : Void or genetic_code id, 1 by default
Args : None or genetic_code id, 1 by default if invalid argument.

cds_count
Title : cds_count
Usage : my $count = $cdtable->cds_count();
Purpose : To retrieve the total number of CDSs used to generate the Codon Table
for that organism.
Returns : an integer
Args : none (if retrieving the value) or an integer( if setting ).

aa_frequency
Title : aa_frequency
Usage : my $freq = $cdtable->aa_frequency('Leu');
Purpose : To retrieve the frequency of an amino acid in the organism
Returns : a percentage
Args : a 1 letter or 3 letter string representing the amino acid

common_codon
Title : common_codon
Usage : my $freq = $cdtable->common_codon('Leu');
Purpose : To retrieve the frequency of the most common codon of that aa
Returns : a percentage
Args : a 1 letter or 3 letter string representing the amino acid

rare_codon
Title : rare_codon
Usage : my $freq = $cdtable->rare_codon('Leu');
Purpose : To retrieve the frequency of the least common codon of that aa
Returns : a percentage
Args : a 1 letter or 3 letter string representing the amino acid

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