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Extract specific peptides from a FASTA file

I hope someone could help me with a simple line command.

I have a protein FASTA file:

>Protein1
sequence 
>protein2
sequence

I want to extract the sequences that has specifics peptides (ERLE). I could do that using grep -A, however it prints the sequence and the header of the below protein. For example, let say the sequence is on protein 1, when I use grep it prints the sequence 1 whit the header of protein 2:

sequence
>Protein2

Is there a way to solve that?

Thank you in advance

protein

Thank you so much. Worked really well

1 answer

Look at -B option for grep.

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