Microcycle sporulation of Streptomyces viridochromogenes

A procedure for submerged culture sporulation of Streptomyces viridochromogenes and S. coelicolor is described. Activated spores were germinated in a complex medium and then shifted to a defined medium containing mineral salts and 2.5 mM L-arginine as carbon and nitrogen source. Sporulation occurred synchronously between 18-24 h incubation. An average of 10 spores were obtained from each original spore in S. viridochromogenes. The microcycle formed spores were nearly identical to surface grown spores with respect to surface morphology, dormancy, germinability and resistance to heat, lysozyme and sonication. The microcycle formed spores differed from surface spores in containing significantly less trehalose, 1.3% compared to 9.7% of the dry weight.