Factor that stimulates resuscitation of dormant cells. Has peptidoglycan (PG) hydrolytic activity. Active in the pM concentration range. Has little to no effect on actively-growing cells. PG fragments could either directly activate the resuscitation pathway of dormant bacteria or serve as a substrate for endogenous Rpf, resulting in low molecular weight products with resuscitation activity (By similarity). Upon overexpression. Not essential; a double rpf1-rpf2 disruption mutant is also viable. The double mutant displays a prolonged lag phase and slower growth after transfer of long-stored cells into fresh medium. Belongs to the transglycosylase family. Rpf subfamily. Extended N-terminus.