Cloning and Characterization of the Tetracycline Resistant Gene, tetB) from Vibrio parahaemolyticus

摘要

A tetracycline resistant Vibrio parahaemolyticus, capable of growing on TCBS medium containing tetracycline, was isolated from cultivated fishes. A gene responsible for the tetracycline resistance was cloned from chromosomal DNA of the V. parahaemolyticus strain using Escherichia coll KAM3, which lacks major multi-drug efflux pumps (DELTA acrB) as host cells. The nucleotide sequence and homology analysis revealed an open reading frame (ORF) for tetracycline resistance protein (TetB). In order to characterize the antibiotic resistance of TetB originated from the V. parahaemolyticus strain, the gene was subcloned into plasmid pSTV28. The resulting plasmid was designated as pSTVTetB and transformated into E. coll KAM3. E. coli KAM3 cells harboring therecombinant plasmid pSTVTetB are able to grow on plates containing tetracycline and oxytetracycline but not doxycycline, indicating that the tetB gene confers the tetracycline- and oxytetracycline-resistance to the host cell.