Hi Careina, just change extension of your sequence file, i.e.: change yoursequencefile.extension (where extension could be .txt .fasta, etc) to yoursequencefile.pir It should work then. Cheers, Albert Albert GUSKOV (Dr) | Research Fellow | Division of Structural & Computational Biology | Nanyang Technological University Proteos 7-01, Biopolis Drive 61, Singapore 138673 Tel: (65) 6586-9690 GMT+8h | Cell: (65) 8366-2779 | Email: [log in to unmask] | Web: www.ntu.edu.sg 2011/2/18 Careina Edgooms <[log in to unmask]>: > Dear CCP4 mailing list > > I have a relatively simple question. How do I get sequence file in .pir > format which is required for many programs? I normally use fasta format but > some programs eg arpwarp do not allow me to use that > > Thanks for your help > > Careina > >