Comparative resistome and virulome analysis of clinical NDM-1-producing carbapenem-resistant Enterobacter cloacae complex

J Glob Antimicrob Resist. 2022 Mar:28:254-263. doi: 10.1016/j.jgar.2022.01.021. Epub 2022 Feb 1.

Abstract

Objectives: The Enterobacter cloacae complex (ECC) are causatives of hospital-acquired infections. The antimicrobial resistance (AMR) and virulence profiling of ECC promotes our knowledge for their elimination in clinical settings.

Methods: We assembled the whole genome of four clinical carbapenem-resistant ECCs and characterized their AMR and virulence profiles using whole genome sequencing.

Results: The chromosomes length scaled from minimum 3 949 952 bp (for P2) to maximum 4 976 575 bp (for P3). Strains P1 and P2 belonged to sequence type (ST)182. P3 and P4 belonged to ST477 and ST134, respectively. The blaCTX-M-15 gene was detected in P1 plasmid. P1 and P4 harboured the blaTEM-1 and blaOXA-1 genes. blaNDM-1 was found in P1, P3, and P4. No blaOXA-48, blaKPC, blaVIM, or blaIMP were identified. The plasmids were nontransferable and had IncFIB, IncFII, Col, and IncC incompatibility (Inc) groups . Class 1 integron was detected in all strains. Virulence genes related to biofilms, adhesins, siderophores (aerobactin, enterobactin, and salmochelin), intrinsic antimicrobial efflux pumps, secretory systems type I to VI, environmental and antibiotic stress response , outer membrane proteins, and heavy metal (copper, tellurite, arsenic, and zinc) resistance were found. The number of positive virulence factors was higher for P1 compared with other strains.

Conclusion: The accumulation of AMR genes in Enterobacter spp. and their high endurance in hostile environments is a serious health problem. More genomic investigations are required to determine their AMR and virulence genetic reservoirs at the global level.

Keywords: Antimicrobial resistance; Carbapenem-resistant Enterobacter cloacae complex; De novo assembly; Virulence.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Carbapenem-Resistant Enterobacteriaceae* / genetics
  • Carbapenems / pharmacology
  • Enterobacter cloacae* / genetics
  • Virulence / genetics
  • beta-Lactamases

Substances

  • Anti-Bacterial Agents
  • Carbapenems
  • beta-Lactamases
  • beta-lactamase NDM-1