FIG. 1.

Schematic representation of the yvyD region in the chromosome of B. subtilis. The yvyD gene is located between the fli operon and the secA gene. A rho-independent terminator is located upstream and downstream of yvyD (7). The locations of the primer pair P1-P2, used for construction of plasmid pKD1, and the primer pair P3-P4, used for the construction of plasmid pKD2, are indicated. The BglII site within yvyD was used for the construction of the yvyD mutant by the insertion of a kanamycin resistance cassette in plasmid pKD1, resulting in plasmid pKD11.