Development of Increased Oxolinic Acid-resistance in Burkholderia glumae

Genomic DNA, partially digested with Sau3AI, of Burkholderia glumae Pg-13, resistant to oxolinic acid (OA), was ligated into pUC118, and Escherichia coli DH5α resistant to 2.5 μg/ml OA was transformed with the plasmid. After incubation on a medium supplemented with 20 μg/ml OA, a clone harboring pB′46 was selected. The nucleotide sequence of the 724-bp insert of pB′46 had no homology to any characterized gene. B. glumae Pg-5, resistant to 10 μg/ ml OA, was transformed with plasmid pUCD3101B′46 containing the insert. An obtained transformant, B25, was resistant to 50 μg/ml OA and had greater resistance to other quinolones than did Pg-5. Transformants of OA-sensitive B. glumae with pUCD3101B′46 had OA sensitivity similar to that of the parental isolates. Received 18 September 2000/ Accepted in revised form 18 October 2000