FIG. 9.

Binding of PcaU to DNA directly downstream from pcaU. Probe (10 ng per reaction mix) was preincubated with 10 μg of protein from E. coli DH5α(pZR22) (lanes 1 through 7) or from E. coli DH5α(pWH661⁺) (lane 8) or without protein (lane 9). Additional components were as follows: 50, 30, and 10 ng of an unlabelled 297-bp PCR DNA fragment from the unrelated vanA gene from Acinetobacter (lanes 1 through 3, respectively); and 50, 30 and 10 ng of the unlabelled PCR fragment used to construct the probe (lanes 4 through 6, respectively). As with PcaU bound to the upstream site, several protein bands were observed, suggesting that bound PcaU exists in oligomeric forms.