Characterization of a Novel Tn7-like Transposon Carrying blaDHA-1 in Providencia stuartii MF1 Isolated from Swine Wastewater.

Providencia stuartii is an emerging pathogen that causes nosocomial infections. In this study, a multidrug-resistant strain P. stuartii MF1 was isolated from swine wastewater. Comprehensive analysis of whole genome sequencing revealed that dozens of antibiotic resistance genes were found in MF1. A novel transposon Tn6450M which has high sequence identity to Tn6450 and the plasmid-borne Tn6765 from Proteus mirabilis was identified in the genome of MF1. Tn6450M was determined to be stably inserted into a new attTn7 site in the P. stuartii MF1 genome and contains the third-generation cephalosporins resistance-associated genes blaDHA-1. Intergeneric transmission of Tn6450 variants poses risks for the spread of antibiotic resistance genes. [ABSTRACT FROM AUTHOR]