FIG. 1.

RT-PCRs with total RNAs prepared from P. stutzeri WM567 grown on hypophosphite as the sole P source to determine the operon structure of ptx. Lanes a, complete RT reactions; lanes b, negative controls for which no reverse transcriptase was added to the reaction; lanes c, PCR-positive controls in which chromosomal DNA was used as the template. The left- and rightmost lanes contain a 100-bp ladder. The junction sequences amplified are indicated above the reactions. For a list of primers used and the predicted PCR product size for each reaction, refer to Table 2.