Single, chemically defined sporulation medium for Bacillus subtilis: Growth, sporulation, and extracellular protease production

Abstract

The composition and application of a single, chemically defined medium for growth and sporulation of Bacillus subtilis is described. At 37°C cells grew with a doubling time of about 40 min; cultures attained near-maximal spore formation (70 to 80% by 12 h after the end of exponential growth and produced 1 x 109 to 2 x 109 heat-resistent free spores at 24 h. Dipicolinic acid production was completed between 7 and 11 h. Cells grown in the single, chemically defined medium excreted levels of serine and neutral proteases comparable to those excreted in nutrient broth medium.