Preferential Compatibility in Streptomyces violaceoruber

Abstract

SUMMARY: A compatibility system, or system of relative mating potency, has been found among mutants of Streptomyces violaceoruber (S. coelicolor). Certain combinations of growth factor-dependent mutants failed to form nutritionally independent (prototrophic) recombinants. Incompatibility was not the result of inability of identical mutant genes to interact, failure of hyphae to fuse, or inhibition of prototroph development by incompatible mixtures. No infective or diffusible factors were found which induced or suppressed fertility. The yield of recombinants was affected by the relative growth rates of the two parental types, the time elapsed between the planting of each parent and the relative and absolute numbers of the parents. Sporogenesis was not a prerequisite for recombination.