The macrolide resistance gene erm(T) was identified for the first time in a porcine Erysipelothrix rhusiopathiae isolate from swine in China. The novel 3,749-bp small plasmid pER29, which carries erm(T), had a G+C content of 31% and four distinct open reading frames. The presence of pER29 increased by at least 128-fold the MICs of clindamycin and erythromycin for E. rhusiopathiae. The fitness cost of pER29 could be responsible for the low frequency of erm(T) in E. rhusiopathiae.
Copyright © 2015, American Society for Microbiology. All Rights Reserved.