Probable terminase small subunit. The terminase lies at a unique vertex of the procapsid and is composed of two subunits, a small terminase subunit and a large terminase subunit. Both terminase subunits heterooligomerize and are docked on the portal protein to form the packaging machine. Once the capsid is packaged with the DNA, the terminase complex is substituted by the connector proteins gp15. Belongs to the skunalikevirus terminase small subunit family.