dfrA20 , a Novel Trimethoprim Resistance Gene from Pasteurella multocida

Abstract
A novel trimethoprim resistance gene, designated dfrA20 , was detected on the 11-kb plasmid pCCK154 from Pasteurella multocida . The dfrA20 gene codes for a dihydrofolate reductase of 169 amino acids. Sequence comparisons revealed that the DfrA20 protein differed distinctly from all dihydrofolate reductases known so far.