Genetic characterization of a novel sequence type of multidrug-resistant Citrobacter freundii strain recovered from wastewater treatment plant

Abstract

A multidrug-resistant Citrobacter freundii strain R17 was isolated from a wastewater treatment plant in China. Whole-genome sequencing of strain R17 revealed a new sequence type (ST412) chromosome (length 5,124,258 bp) and an Inc FII (Yp) group plasmid pCFR17_1 (length 206,820 bp). A total of 13 antibiotic-resistance genes (ARGs) that confer resistance to eight different antibiotic groups were encoded by strain R17 and 12 of them were carried by plasmid pCFR17_1. These data and analysis suggest that the environment-derived C. freundii strains may serve as potential sources of ARGs and highlight the need of further surveillance of this bacteria in the future.

Keywords:

• Citrobacter freundii
• multidrug resistant
• antibiotic-resistance genes
• whole-genome sequencing
• wastewater treatment plant
• insertion elements

Acknowledgments

We would like to thank Dr. Wenwu Zhang for his assistance in sampling. This work was supported by research grants from the National Key Research and Development Program of China (No. 2016YFD0501105); National Natural Science Foundation of China (Nos. 41406140 and 81741098); and Zhejiang Provincial Natural Science Foundation of China (No. LY17H190003).

Disclosure

The authors report no conflicts of interest in this work.