Further studies on the competence development in exponentially growing cultures of Bacillus subtilis.

Bacillus subtilis, growing in Bott and Wilson's medium, develops two peaks of competence in batch cultures. The first maximum developed during the exponential growth phase and it has been studied comparatively with the competence level reached in continuous culture at Dt = 2.5 h. In both cases, 100 microgram/ml of arginine inhibited competence. Continuous cultures treated with arginine recovered competence specifically after the addition of Mn2+. In addition, a reduction in the synthesis of aconitase and fumarase was observed in the arginine-inhibited continuous cultures.