Probably localized either on the surface of the outer spore membrane and/or in the inner spore coat. Expressed in the mother cell compartment from T5 of sporulation. LysM domains are thought to be involved in peptidoglycan binding. Expression of ykvP is regulated by SigK and dependent on GerE. Inactivation of the ykvP gene does not affect vegetative growth, spore resistance to heat, chloroform and lysozyme, or spore germination in the presence of L-alanine.