colicinogen /kol′isin″əjən/ [(E.) coli + L, caedere, to kill; Gk, genein, to produce] , an extrachromosomal segment of DNA in some strains of Escherichia coli that induces secretion of a colicin, a protein lethal to other strains of the bacterium. Colicins attach to specific receptors on the cell membrane and impair the synthesis of macromolecules or the production of energy. Also called colicinogenic factor.
