All PCR reactions were performed in 50 L volumes containing
0.2 M of each primer pair in 10 mM Tris-HCl (pH 9.0), 50 mM KCl, 1.5
mM MgCl2, 200 M of each dNTP, 0.1% TritonX-100, 0.5 U Taq
Polymerase (Promega, Madison, WI) and with approximately 105 bacteria.
A