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adit sequences ID

Hi guys,

I have two files, a fasta file (containing a sequences and sequence IDs) and a text file containing a list of sequence ID.

I would like to extract the respective sequence for each of the sequence IDs in the text file. then I searched the net and found the following commend can do the job:

cut -c 2- EXAMPLE.TXT | xargs -n 1 samtools faidx EXAMPLE.FA

I used it, but it gives me the error message like this :

[fai_fetch] Warning - Reference omp2352_c1_seq1 not found in FASTA file, returning empty sequence
xargs: samtools: terminated by signal 11

My fasta file is like this:

>comp904_c0_seq2 len=1452 path=[4675:0-87 7837:88-89 7839:90-96 6352:97-97 6299:98-1223 5917:1224-1227 5921:1228-1451]
TCTAATAAACCATCCATTCATTCACACCACCACTCTTGCTCATTGGAGACACCATGCACT
AATCAAAAAAAAAACCTTAATGTATATTAAAAAAAAATAATAGCGGGAGGAGGAAGAGAC
GGGAGGGGCTTTTCTATCAAGCTTTTCTCATAAATAATACCGAAAGTACGATCAAATTTT
TCTCATTGTTTTTCTTGCTGTGATAGAAAAAGATGCGCGCGTGCCGAACGAGGGGAAACG
GGGAAACAAGAGAGAACGAAGAAAAGGGAACAAGGATGAAAAATAAATCGCTCATCGTAC
AACACGAGAGGACAAAAGGGTCGTAAATAGTAATAGTAGTAATAGTAAGTAAGTAAATAG
GAGGAGAGGCTCTCTCATTCATACAAATTGAGACAAACAGATACAATATAGAGTTACGGC
TAAGATAATTATAATAATACAGTATGTACTGGGATCGAGACGGTTCCCGTCTCTGATTCA
AATGTCTCTGTGGGCCTGGCCCGCACTACACAGCACTGTTAGAGTTCGTAATTTTTATTT
TATTTTTATTTTTTTTTAATAATGTGTGGAGATGATTGTGTCGTTCGCAAGTTACGACAC
GTCCTGGTCCTCTACGTCCTGGAGTTGTTCTTTGGGTTCCGCTTCTCCGTCCCCTTGCAT
ATCACTGGTCCACAGCGTCAGGTTGTCGCGCAACAGTTGCATGATCAACGTGCTGTCTTT
ATAGCTCTCCTCGGATAAAGTGTCTAGTTCTGCAATGGCGTCGTCGAAGGCGGCTTTCGC
TAGACGACAGGCCCTGTCCGGACTGTTCAATATTTCGTAATAGAATACGGAGAAATTAAG
GGCCAATCCGAGCCTGATCGGATGAGTGGGTGGCAGTTCTGTCATTGCGATATCACTGGC
TGATTTGTAAGCGACCAACGAATGTTCAGCGGCGTCTTTACGGTCGTTGCCTGTCGCGAA
TTCGGCCAGATATCGGTGGTAGTCACCCTTCATTTTGTAATAAAACACTTTAGATTCGCC
CGTGGAAGCCGCCGGGATAAGATGTTTGTCCAAAACGGCCAATATATCCGAACAGATGTC
CCTCAACTCCTTCTCCACCTGCGCCCGGTACTGCCTTATCATCTCCAACTTGTCGTCCGT
CCCTTTGCTCTCTTCTTTCTGTTCGATCGAGGAGATTATACGCCAAGAAGCCCTCCGTGC
ACCTATCACGTTCTTGTAAGCGACAGAAAGAAGGTTTCGCTCCTCCACGGTCAGCTCCAG
GTCCAGCTTGGCCACCTTCTTCATAGCGTCCACCATTTCATCGTAACGTTCGGCCTGCTC
CGCCAGTTTCGCCTTGTAGACGTTATCCTCCCGTTCAGACATATTGCGATGATTACCGAT
TGAAACTCCACAACAACACTTTATTCACTCGAGACACTCCGCGTACTGCCAATATGGCCG
CGCCCGAGATCG

ID list file like this:

comp2352_c1_seq1
comp3842_c0_seq2
comp3842_c0_seq4
comp3842_c0_seq6
comp2145_c1_seq3
comp2145_c1_seq4
comp5304_c1_seq5
comp5696_c0_seq18
comp5237_c0_seq5
comp5237_c0_seq7
comp7076_c0_seq2

I am new at kind of work. could any one give me some suggestions!

How could I make the samtools work? should I change the form of sequences ID in both file?

e.g. for the first file(fasta file) just keep the >comp904_c0_seq2 part, erase the rest from the ID?

For ID.txt file should I add > before the each sequence's ID?

If that works, how can I do that? because there r many sequences in fasta file , it is hard to do that one by one?

sequence
• 3,581 views • link
updated by Ram Ram • written by Kurban Kurban

The error is because you do not have '>' in your IDs file. Instead of the cut, just use a cat.

• 0 views • link
written by Ram Ram

thanks @RamRS, yeah, after add ">" , it worked fine.

• 0 views • link
written by Kurban Kurban

You could use sed:

sed -re 's/^/>/' <EXAMPLE.TXT | xargs -n 1 samtools faidx EXAMPLE.FA
• 0 views • link
written by Ram Ram

1 answer

I wrote a piece of Perl code for this some time back. Here you go: https://github.com/RamRS/myPerlScripts/blob/master/filterMulFa.pl

If you prefer Python (or would like to extract a sequence multiple times if an ID is seen multiple times in the ID file), this should help: https://github.com/RamRS/myPyScripts/blob/master/extract_fa_subset.py

• 0 views • link
written by Ram Ram

Thanks @RamRS.

but could u give it a look at this :

kurban@kurban-X550VC:~/Desktop$ ls
22.pl  22.pl~  gene.fasta  my.pl  my.pl~  tf.IDs
kurban@kurban-X550VC:~/Desktop$ perl my.pl gene.fasta tf.IDs
Can't locate Getopt/ArgParse.pm in @INC (you may need to install the Getopt::ArgParse module) (@INC contains: /etc/perl /usr/local/lib/perl/5.18.2 /usr/local/share/perl/5.18.2 /usr/lib/perl5 /usr/share/perl5 /usr/lib/perl/5.18 /usr/share/perl/5.18 /usr/local/lib/site_perl .) at my.pl line 5.
BEGIN failed--compilation aborted at my.pl line 5.

what is it say?

by the way I am using ubuntu 14.04

• 0 views • link
updated by Ram Ram • written by Kurban Kurban

Ah, you need to install Getopt::Argparse using CPAN. Open up a new terminal, and type:

$ cpan
cpan> install cpan
cpan> reload cpan
cpan> install Getopt::Argparse
cpan> install CJFIELDS/BioPerl-1.6.901.tar.gz
• 0 views • link
written by Ram Ram

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