I haven't read the Bio::DB::GenBank documentation (please feel free to do so ;-), but I suspect that write_sequence is a method of that class and so maybe needs to be called something like
    $gb->write_sequence( ">>roar.fa", 'fasta', $seq );

Give a man a fish:  <%-{-{-{-<

In reply to Re^5: Get Fasta file with Protein Sequences given a file with Genbank Ids using Perl by AnomalousMonk
in thread Get Fasta file with Protein Sequences given a file with Genbank Ids using Perl by dimitris852

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