Genome-Based Analysis of a Multidrug-Resistant Hypervirulent Klebsiella pneumoniae

Area of Science:

• Microbiology
• Genetics
• Infectious Diseases

Background:

• Multidrug-resistant hypervirulent Klebsiella pneumoniae (MDR-hvKP) is an emerging global health threat.
• The co-existence of high virulence and antimicrobial resistance in K. pneumoniae complicates clinical management.
• Understanding the molecular mechanisms driving MDR-hvKP spread is crucial for effective control.

Purpose of the Study:

• To characterize the molecular features of MDR-hvKP strains, focusing on plasmid transferability.
• To investigate the genetic basis of virulence and drug resistance in a specific MDR-hvKP isolate (hvKP247).
• To elucidate the mechanisms of co-transfer for virulence and resistance genes.

Main Methods:

• Whole-genome sequencing of the MDR-hvKP strain hvKP247 (ST5214, K1).
• Analysis of sequence types (STs) among 30 clinical hvKP isolates.
• Conjugation experiments to assess plasmid transferability.

Main Results:

• Identified two novel STs (ST5570, ST5571) among clinical isolates.
• hvKP247 harbors two transferable plasmids: a self-transferable hybrid virulence plasmid (pHvKP247-vir) and a drug-resistant plasmid (pHvKP247-MDR).
• The drug-resistant plasmid is indirectly transferred via the virulence plasmid, with virulence genes located on both plasmids and chromosomal elements.

Conclusions:

• The hybrid virulence plasmid and drug-resistant plasmid can co-transfer, promoting the simultaneous dissemination of virulence and resistance.
• This highlights the critical need for increased public awareness regarding the combined spread of these traits in MDR-hvKP.
• Findings underscore the importance of monitoring and controlling MDR-hvKP to mitigate public health risks.