I may be missing this, but is there object access to the isoelectric point of a protein sequence? Jay -- _______________ Jay Hesselberth University of Texas Ellington Lab 2500 Speedway MBB 3.424 / A4800 Austin, TX 78712 Work: (512) 471-6445 Fax: (512) 471-7014 Email: jhessel@mail.utexas.edu Web: http://slacker.icmb.utexas.edu/jhessel