Genomic Study of blaIMI-Positive Enterobacter cloacae Complex in Singapore over a Five-Year Study Period

Sophie Octavia; Tse Hsien Koh; Oon Tek Ng; Kalisvar Marimuthu; Indumathi Venkatachalam; Raymond T P Lin; Jeanette W P Teo

doi:10.1128/AAC.00510-20

Genomic Study of bla_IMI-Positive Enterobacter cloacae Complex in Singapore over a Five-Year Study Period

Antimicrob Agents Chemother. 2020 Jul 22;64(8):e00510-20. doi: 10.1128/AAC.00510-20. Print 2020 Jul 22.

Authors

Sophie Octavia^{1

2}, Tse Hsien Koh³, Oon Tek Ng^{2

4

5}, Kalisvar Marimuthu^{2

5

6}, Indumathi Venkatachalam^{7

8}, Raymond T P Lin^{1

2

9}, Jeanette W P Teo¹⁰

Affiliations

¹ National Public Health Laboratory, National Center for Infectious Diseases, Singapore.
² National Centre for Infectious Diseases, Singapore.
³ Singapore General Hospital, Department of Microbiology, Singapore.
⁴ Tan Tock Seng Hospital, Department of Infectious Diseases, Singapore.
⁵ Nanyang Technological University, Lee Kong Chian School of Medicine, Singapore.
⁶ National University of Singapore, Yong Loo Lin School of Medicine, Singapore.
⁷ Singapore General Hospital, Department of Infectious Diseases, Singapore.
⁸ Singapore General Hospital, Department of Infection Prevention & Epidemiology, Singapore.
⁹ National University Hospital, Department of Laboratory Medicine, Singapore.
¹⁰ National University Hospital, Department of Laboratory Medicine, Singapore Jeanette_Teo@nuhs.edu.sg.

Abstract

The bla_IMI gene is rarely detected outside the Enterobacter genus. Genomic characterization of 87 bla_IMI-positive Enterobacter cloacae complex members revealed that the largest phylogenomic clade was made up of E. cloacae subsp. cloacae (71.3%), followed by the newly described species E. bugandensis (13.8%), E. sichuanensis (10.3%), and E. roggenkampii (4.6%). IMI-1 was the predominant carbapenemase variant (86/87, 98.9%). All the bla_IMI genes were associated with chromosomally integrated Xer-dependent integrative mobile elements (IMEXs), with two new variants detected.

Keywords: Enterobacter; Enterobacteriaceae; antimicrobial resistance; carbapenemase; imipenemase; phylogenomics; whole genome.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / pharmacology
Bacterial Proteins / genetics
Enterobacter cloacae* / genetics
Enterobacteriaceae Infections* / epidemiology
Genomics
Humans
Microbial Sensitivity Tests
Singapore / epidemiology
beta-Lactamases / genetics

Substances

Anti-Bacterial Agents
Bacterial Proteins
beta-Lactamases