解析GenBank文件:获取locus标签与产品

时间:2014-02-27 11:55:38

标签: python perl parsing bioperl genbank

基本上,GenBank文件包含基因条目('gene'后面跟着相应的'CDS'条目(每个基因只有一个),就像我在下面显示的两个一样。我想得到locus_tag vs product in a制表符分隔的两个列文件。'gene'和'CDS'总是先后跟空格。

A previous question suggested a script.

问题在于,似乎因为'product'在其名称中有时带有'/'字符,它与此脚本存在冲突,据我所知,使用'/'作为字段分隔符来存储数组中的信息?

我想解决这个问题,无论是修改此脚本还是构建其他脚本。

perl -nE'
  BEGIN{ ($/, $") = ("CDS", "\t") }
  say "@r[0,1]" if @r= m!/(?:locus_tag|product)="(.+?)"!g and @r>1
' file


 gene            complement(8972..9094)
                 /locus_tag="HAPS_0004"
                 /db_xref="GeneID:7278619"
 CDS             complement(8972..9094)
                 /locus_tag="HAPS_0004"
                 /codon_start=1
                 /transl_table=11
                 /product="hypothetical protein"
                 /protein_id="YP_002474657.1"
                 /db_xref="GI:219870282"
                 /db_xref="GeneID:7278619"
                 /translation="MYYKALAHFLPTLSTMQNILSKSPLSLDFRLLFLAFIDKR"
 gene            68..637
                 /locus_tag="HPNK_00040"
 CDS             68..637
                 /locus_tag="HPNK_00040"
                 /codon_start=1
                 /transl_table=11
                 /product="NinG recombination protein/bacteriophage lambda
                 NinG family protein"
                 /protein_id="CRESA:HPNK_00040"
                 /translation="MIKPKVKKRKCKCCGGEFKSADSFRKWCSAECGVKLAKIAQEKA
                 RQKAIEKRNREERAKIKATRERLKSRSEWLKDAQAIFNEYIRLRDKDEPCISCRRFHQ
                 GQYHAGHYRTVKAMPELRFNEDNVHKQCSACNNHLSGNITEYRINLVRKIGAERVEAL
                 ESYHPPVKWSVEDCKEIIKTYRAKIKELK"

2 个答案:

答案 0 :(得分:2)

由于您的示例GenBank文件不完整,我上网查找可以在示例中使用的示例文件,我找到了this file

使用此代码和Bio::GenBankParser模块,解析了猜测结构的哪些部分。在这种情况下,“功能”包含locus_tag字段和product字段。

use strict;
use warnings;
use feature 'say';
use Bio::GenBankParser;

my $file = shift;
my $parser = Bio::GenBankParser->new( file => $file );
while ( my $seq = $parser->next_seq ) {
    my $feat = $seq->{'FEATURES'};
    for my $f (@$feat) {
        my $tag = $f->{'feature'}{'locus_tag'};
        my $prod = $f->{'feature'}{'product'};
        if (defined $tag and defined $prod) {
            say join "\t", $tag, $prod;
        }
    }
}

<强>用法:

perl script.pl input.txt > output.txt

<强>输出:

MG_001  DNA polymerase III, beta subunit
MG_470  CobQ/CobB/MinD/ParA nucleotide binding domain-containing protein

同一输入的单行输出将是:

MG_001  DNA polymerase III, beta subunit
MG_470  CobQ/CobB/MinD/ParA nucleotide binding
                     domain-containing protein

当然假设您将/s修饰符添加到正则表达式以考虑多行条目(评论中指出leeduhem):

m!/(?:locus_tag|product)="(.+?)"!sg
#                                ^---- this

答案 1 :(得分:1)

阅读了重复的问题http://www.biostars.org/p/94164/(请不要像这样发帖),这是一个最小的Biopython答案:

import sys
from Bio import SeqIO
filename = sys.argv[1] # Takes first command line argument input filename
for record in SeqIO.parse(filename, "genbank"):
    for feature in record.features:
        if feature.type == "CDS":
            locus_tag = feature.qualifiers.get("locus_tag", ["???"])[0]
            product = feature.qualifiers.get("product", ["???"])[0]
            print("%s\t%s" % (locus_tag, product))

通过微小的更改,您可以将其写入文件中。