Seqret reads in a sequence, and writes it out, in the format that you need. It is probably the most commonly used EMBOSS program. You do not need any format converter, use seqret!

Use the name of the sequence to fetch from a teaching database installed in wEMBOSS.

Click on “from the EMBOSS databases or a current project file.

on the field: filename or USA write:

tembl:xlrhodop

this is the way of retrieving sequences from databases in EMBOSS, dababasename:sequence

Output sequence [xlrhodop.fasta]:

Look at the resulting file.

B- Now let's retrieve the sequence using its the accession number:

To access a sequence from a database, enter the USA here: tembl:L07770

You should get the same sequence:

Look at the result: