This protein is involved in host lysis. This family is not considered to be a peptidase according to the MEROPs database. This family Rz and the Rz1 protein (Pfam:PF06085) represent a unique example of two genes located in different reading frames in the same nucleotide sequence, which encode different proteins that are both required in the same physiological pathway [1].

1: Complementation and characterization of the nested Rz and Rz1 reading frames in the genome of bacteriophage lambda. Zhang N, Young R; Mol Gen Genet. 1999;262:659-667. PMID:10628848