Work

ST11 carbapenem-resistant Klebsiella pneumoniae integrates virulence plasmid fragments into the chromosome via insertion sequence

Year: 2025

Type: article

Abstract: Virulence plasmids are key drivers of hypervirulence in Klebsiella pneumoniae . Here, we report a systematic analysis of chromosomal integration of a p17-15vir-derived fragment carrying virulence ( rmpA2 and iutA - iucABCD ) and resistance genes in nine bla KPC−2 -positive ST11-KL47 carbapenem-resistant K. pneumoniae (CRKP) isolates. Of these, seven exhibited a hypervirulent phenotype in a mouse infection model. Nanopore sequencing analysis revealed that these virulence-associated integration regions could be classified into three distinct groups based on their structural patterns. Notably, we investigated the mechanisms underlying the formation of the integration region and proposed an IS 26 -mediated model for the integration of virulence gene-carrying plasmid fragment into the chromosome. Besides, IS Kpn1 was identified for the first time as a preferred insertion hotspot. Both bla KPC−2 and rmpA2 demonstrated stable persistence in these isolates without antibiotic selection pressure, and group I integration regions displayed the capability to form circular intermediates. These findings provide critical insights into the virulence plasmid fragment integrated into their chromosomes and underscore the importance of surveillance for such hybrid threats.

Source: BMC Microbiology

DOI: 10.1186/s12866-025-04235-6

Authors: Xu Liu, Lijuan Xu, Huiyue Dong, Shangshang Qin, Yan Li, Hong Yao

Institutions: First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Ministry of Agriculture and Rural Affairs, Henan Agricultural University

Language: English

Topic: Antibiotic Resistance in Bacteria

Subfield: Molecular Medicine

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,990