Kappa particles | definition of kappa particles by Medical dictionary
inheritable cytoplasmic symbionts, once thought to be particles mainly or exclusively of DNA, occurring in some strains of Paramecium; capable of producing a product lethal to other strains.
kappa particles the bacteria that inhabit the cytoplasm of the ciliate Paramecium aurelia. Kappa-free Paramecia are sensitive to toxins produced by the particles, dying when exposed to them, after CONJUGATION. Kappa carriers (called killer stocks) are immune to the toxin.