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split all fasta sequences in a multi fasta file from half into two sequences

Hi i have a fasta file with many fasta sequences and I want to split all the fasta sequences into two half from middle.. I am new to bioinformatics kindly suggest some tool or perl command

sequence
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updated by 5heikki 5heikki • written by manishbiotechie • manishbiotechie

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written by lakhujanivijay lakhujanivijay

I know how to split a big fasta files into multiple fasta files but my query is to bisect all fasta nucleotide sequences in a fasta file into two halves e.g.

>TC93917
GGCACGAGGCAGAAACCAATTTCAAAACATTATATAAATAGCTAGTTTCAGTACTAGCTG
TGCAACTCAATTATAGAACAATGGCTTCCTCTATGATCTCCTCTTCAGCTATCACTACAG
TTAACCGTGCCTCTCCGGTACAATCCGGTGCGGTGGCTCCATTCGTCGGACTCAAGTCCA
TGGCTGGCTTCCCAATTACAAAGGTCAACAAAGACATTACCTCCATTACAAGCAATGGTG
GAAGAGTAAACTGCATGCAGGTGTGGCCTCCTATTGGCAAGAAGAAGTTTGAGACTCTTT
CATATCTTCCACCATTGACCAGAGAACAATTGGCGAAAGAAGTTGAATACCTTATAAGGA
AGGGATGGGTTGCTTGCTTGGAATTCGAGACCGAGAAAGGATTTGTGTACCGTGAGAACC
ACAGTTCACCAGGATACTATGACGGACGTTACTGGACAATGTGGAAGTTGCCTTTGTTTG
GAGCAACTGATGCTTCTCAAGTGTTGAAGGAGCTTGATGAAGTTGTTGCTGCTTACCCTA
CTGCCTTTGTCCGTATCATCGGATTCGACAATGTTCGTCAAGTTCAATGCATCAGTTTCA
TTGCACACACACCTGATGTTTACTAAGTTCATTGCACTGGAATTTGGAAGAACTTTTTTC
TTCTTCCCATTTATGTTTTGCTTTTAATTTCCATTTCTTTTTCAGGGAAATGTTTTCCTT
CTGTGTTTTTATATTTCTGTTTTTGGATTTGAAAAATGGGATGTATAAGATTAAGAGTTA
ATGAATGAAATGGTTACTTAATTCCCAAAGTACTTAAAAGAATCCATTATCTATGTAGTT
TTCCTTGTTCTGC

into

>TC93917_1
GGCACGAGGCAGAAACCAATTTCAAAACATTATATAAATAGCTAGTTTCAGTACTAGCTG
TGCAACTCAATTATAGAACAATGGCTTCCTCTATGATCTCCTCTTCAGCTATCACTACAG
TTAACCGTGCCTCTCCGGTACAATCCGGTGCGGTGGCTCCATTCGTCGGACTCAAGTCCA
TGGCTGGCTTCCCAATTACAAAGGTCAACAAAGACATTACCTCCATTACAAGCAATGGTG
GAAGAGTAAACTGCATGCAGGTGTGGCCTCCTATTGGCAAGAAGAAGTTTGAGACTCTTT
CATATCTTCCACCATTGACCAGAGAACAATTGGCGAAAGAAGTTGAATACCTTATAAGGA
AGGGATGGGTTGCTTGCTTGGAATTCGAGACCGAGAAAGGATTTGTGTACCGTGAGAACC
ACAGTTC

>TC93917_2
ACCAGGATACTATGACGGACGTTACTGGACAATGTGGAAGTTGCCTTTGTTTG
GAGCAACTGATGCTTCTCAAGTGTTGAAGGAGCTTGATGAAGTTGTTGCTGCTTACCCTA
CTGCCTTTGTCCGTATCATCGGATTCGACAATGTTCGTCAAGTTCAATGCATCAGTTTCA
TTGCACACACACCTGATGTTTACTAAGTTCATTGCACTGGAATTTGGAAGAACTTTTTTC
TTCTTCCCATTTATGTTTTGCTTTTAATTTCCATTTCTTTTTCAGGGAAATGTTTTCCTT
CTGTGTTTTTATATTTCTGTTTTTGGATTTGAAAAATGGGATGTATAAGATTAAGAGTTA
ATGAATGAAATGGTTACTTAATTCCCAAAGTACTTAAAAGAATCCATTATCTATGTAGTT
TTCCTTGTTCTGC

sorry if i asked this simple thing but as i told i am new to bioinfo

• 1 views • link
updated by lakhujanivijay lakhujanivijay • written by manishbiotechie • manishbiotechie

Hello manishbiotechie,

Please use the formatting bar (especially the code option) to present your post better. I've done it for you this time.
code_formatting

I know how to split a big fasta files into multiple fasta files

You should explain this by adding your code here. May be people can suggest how you can edit / expand your code.

• 1 views • link
written by lakhujanivijay lakhujanivijay

Why do you need to [literally] split the sequence in half? It should be possible to do with awk.

• 1 views • link
written by Kevin Blighe Kevin Blighe

1 answer

Assuming no linebreaks in sequences:

awk '{if(/^>/){H1=$0"_1";H2=$0"_2"}else{print H1"\n"substr($0,1,length($0)/2)"\n"H2"\n"substr($0,length($0)/2+1)}}' seq.fa
• 0 views • link
written by 5heikki 5heikki

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