Emergence of blaIMI-2- and blaIMI-16-Producing Enterobacter asburiae in the Aquaculture Environment of Jiangsu, China

Jie Che; Zhaoran Wang; Yuqin Song; Hongxia Guan; Min Yuan; Xia Chen; Xiaofei Zhao; Yong Xiao; Yunfei Zhang; Dan Sha; Chao Wang; Jie Feng; Juan Li

doi:10.1128/spectrum.02853-22

Emergence of bla_IMI-2- and bla_IMI-16-Producing Enterobacter asburiae in the Aquaculture Environment of Jiangsu, China

Microbiol Spectr. 2023 Mar 6;11(2):e0285322. doi: 10.1128/spectrum.02853-22. Online ahead of print.

Authors

Jie Che^#¹, Zhaoran Wang^#^{2

3}, Yuqin Song^#², Hongxia Guan^#⁴, Min Yuan¹, Xia Chen¹, Xiaofei Zhao¹, Yong Xiao⁴, Yunfei Zhang¹, Dan Sha⁴, Chao Wang², Jie Feng², Juan Li¹

Affiliations

¹ State Key Laboratory for Infectious Diseases Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Disease, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
² State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
³ College of Life Science, University of Chinese Academy of Sciences, Beijing, China.
⁴ Wuxi Center for Disease Control and Prevention, Wuxi, China.

^# Contributed equally.

Abstract

Carbapenem-resistant Enterobacteriaceae strains have emerged as a serious threat to global public health. In recent years, bla_IMI, a carbapenemase gene that drew less attention before, has been increasingly detected in both clinical and environmental settings. However, the environmental distribution and transmission of bla_IMI, especially in aquaculture, require systematic investigation. In this study, the bla_IMI gene was detected in fish (n = 1), sewage (n = 1), river water (n = 1), and aquaculture pond water samples (n = 17) collected from Jiangsu, China, demonstrating a relatively high sample-positive ratio of 12.4% (20/161). Thirteen bla_IMI-2- or bla_IMI-16-carrying Enterobacter asburiae strains were isolated from bla_IMI-positive samples of aquatic products and aquaculture ponds. We also identified a novel transposon (Tn7441) carrying bla_IMI-16 and a conserved region containing several truncated insertion sequence (IS) elements harboring bla_IMI-2, all of which may play important roles in bla_IMI mobilization. The occurrence of bla_IMI-carrying Enterobacter asburiae in aquaculture-related water samples and fish samples highlights the risk of transmission of bla_IMI-carrying strains through the food chain and the need for effective measures to prevent further dissemination. IMPORTANCE IMI carbapenemases have been detected in clinical isolates of many bacterial species with systemic infection and cause a further burden on clinical treatment in China, but their source and distribution are still unclear. The study systematically investigated the distribution and transmission of the bla_IMI gene in aquaculture-related water bodies and aquatic products in Jiangsu Province, China, which is famous for its rich water resources and developed aquaculture industry. The relatively high prevalence of bla_IMI in aquaculture samples and the identification of novel mobile elements harboring bla_IMI enhance our knowledge of bla_IMI gene distribution and highlight the public health risk and urgency of surveillance of aquaculture water systems in China.

Keywords: Enterobacter asburiae; aquaculture environment; blaIMI; novel transposon Tn7441.