Pfam
Pfam is a protein database which allows the user to search for functional regions (domains) of a protein sequence [1]. Pfam release version 26.0 is comprised of more than 13K protein families and 499 clans[2]. To successfully locate a protein of interest Pfam utilizes a scoring algorithm similar to other databases such as BLAST, Prosite and SMART. In order to pin-point a specific domain on the query, a gathering threshold (GA) is assigned to each protein family added by Pfam executives into the database[3]. GA mainly operates under maximum coverage criteria [4].