Analysis of the inhibition of sporulation of Bacillus subtilis caused by increasing the number of copies of the spo0F gene.

The Bacillus subtilis spo0F gene was cloned on a 6.3 kbp Bg/II fragment. The effect on sporulation of amplification of the spo0F region was examined. Sporulation was inhibited to less than 5% of that of the parental strain when as few as four copies of the spo0F region were present. Subclones, constructed in autonomous or integrative vectors, were used to demonstrate that the region responsible for the copy-number-dependent asporogeny corresponded closely with the spo0F structural gene. A possible mechanism for this effect is discussed.