Phage capsid scaffolding protein (GPO) serine peptidase
This family consists of several bacteriophage capsid scaffolding proteins (GPO) and some related bacterial sequences. GPO is thought to function in both the assembly of proheads and the cleavage of GPN. The family is found to function as a serine peptidase, with a conserved Asp, His and Ser catalytic triad, as in subtilisin, and as represented in MEROPS:S73. The family includes capsid assembly scaffolding protein from Enterobacteria phage P2 which cleaves itself and then becomes the scaffold protein upon which the bacteriophage prohead is built - a mechanism quite common amongst phages.