Heterogeneous Clones ("Heteroclones") in Streptomyces Coelicolor a 3(2).

C E R T A I N recombinant colonies of Streptomyces coelicolor ( S . violaceoruber according to KUTZNER and WAKSMAN 1959) display a mixture of different phenotypes ( SERMONTI and SPADA-SERMONTI 1959). Experimental conditions have been successfully established for the recovery of such colonies, and a convenient method has been developed for the genetical analysis of S. coelicolor. To describe these colonies and their descendants, it has been necessary to adopt a new term: “heteroclone,” which describes a clone stemming from a genetically heterogeneous and highly unstable original unit. This term can readily be applied to the descendants of a bacterial zygote (LEDERBERG 1957; ANDERSON 1958).