The role of phage in the transduction of the toxinogenic factor in Corynebacterium diphtheriae.

Abstract

SURMMARY Strains of Corynebacterium diphtheriae which produced large amounts of toxin (e.g. pw8) were found to be non-lysogenie, but they contained a cytoplasmic toxinogenic factor designated as T+. After infection with phage they produced less toxin. It is possible to remove the phage from the lysogenic strains without affecting the T+ factor by treatment with small amounts of acriflavine. When treated with larger amounts of acriflavine the T+ factor was also removed, rendering the strain non-toxinogenic. The toxin-inducing phages can be converted in vitro into non-toxinogenic phages by treatment with small amounts of acriflavine. After passage through the pw8t + strains these phages revert to toxin-inducing ability. Similarly, the naturally occurring, non-toxinogenic γ phage can be made to induce toxin production. This indicates that the role of phage in diphtheria toxin production is to transduce the T+ factor.