Table 1.
MICs and percentages of bacitracin resistance of C. perfringens isolates.
Figure 1.
Comparison between the C. perfringens bcrABDR genes, the E. faecalis bcrABD operon and the B. licheniformis bcrABC operon.
Organization of C. perfringens c1261_A resistance genes bcrA, bcrB, bcrD, and bcrR and comparison with the bcrABD operon of E. faecalis ARO1/DCVS (AY496968) and the bcrABC operon of B. licheniformis ATCC 9945A (L20573). Open arrows indicate ORFs. The amino acid percentages indicated relate to the identity between the amino acid sequences of the proteins encoded by the ORFs. The bcrABC operon of B. licheniformis is inverted to facilitate the comparison.
Table 2.
Bacitracin MIC values (µg/mL) of C. perfringens strain c1261_A grown with different concentrations of efflux pump inhibitors.
Figure 2.
Expression and cotranscription of bcrABDR genes in presence of bacitracin.
A) Semi-quantitative RT-PCR analysis of strain c1261_A grown in various concentrations of bacitracin. Expression of 16S rRNA gene (rrn) was used as a control. B) Amplification of intergenic regions by RT-PCR of strain c1261_A grown in presence of 256 µg/mL of bacitracin. Lane L, DNA ladder; Lane 1, bcrA; Lane 2, bcrB; Lane 3, bcrD; Lane 4, bcrR; Lane 5, bcrD/bcrB intergenic region; Lane 6, bcrB/bcrA intergenic region; Lane 7, bcrA/bcrR intergenic region.
Figure 3.
PFGE and hybridization analysis of I-CeuI and MluI double-digested DNA of the bacitracin resistant C. perfringens strain c1261_A.
PFGE analysis of C. perfringens strain c1261_A total DNA (A). Southern blot of C. perfringens isolate c1261_A total DNA probed with rrn (B) and with bcrB (C). Sizes (in kilobases) are indicated on the left.