Genomic insights into a complete deletion of the mgrB locus in colistin-resistant Klebsiella pneumoniae ST2268 isolated from a human infection. (December 2021)

• Record Type: Journal Article
• Authors: Song, Yunjia; Yang, Jinge; Ju, Yingjiao; Liu, Dejun; Wang, Yang; Sun, Xutao; Lv, Yuan
• Is Part Of: Journal of global antimicrobial resistance. Volume 27(2021)
• Page Start: 75
• Page End: 78
• Publication Date: 2021-12
• Subjects: Colistin resistance -- mgrB -- Whole-genome sequencing -- Klebsiella pneumoniae -- Nosocomial infection; Drug resistance -- Periodicals; Drug resistance -- Periodicals; Drug resistance; Periodicals; 616.9041
• DOI: 10.1016/j.jgar.2021.07.004
• Languages: English
• ISSNs: 2213-7165

Abstract

Highlights: Whole-genome sequence of Klebsiella pneumoniae ST2268 with high colistin resistance isolated from a patient. Inactivation of mgrB is one of the commonest mutational mechanisms conferring colistin resistance in clinical isolates. A large 20.3-kb deletion including complete deletion of mgrB in colistin-resistant K. pneumoniae P094-1 was identified. Colistin resistance was conferred by IS 1 -induced total deletion of mgrB . ABSTRACT: Objectives: The emergence of colistin-resistant Klebsiella pneumoniae (CoRKp) is a serious public-health issue as colistin is the last line of defence against infections caused by multidrug-resistant Gram-negative bacteria. In this study, we generated a draft genome sequence for CoRKp strain P094-1 isolated from a sputum sample of an infected patient. Methods: Whole genomic DNA of strain P094-1 was sequenced using a PacBio sequencing platform. Generated reads were de novo assembled using Hierarchical Genome Assembly Process (HGAP) v.3.0. Colistin resistance-related genes were predicted from the genome sequence and were validated experimentally. Results: The genome of strain P094-1 lacked a 20.3-kb region, including complete deletion of the mgrB gene. Molecular and genome sequencing-based analyses revealed that the observed colistin resistance of P094-1 could not be attributed to plasmid-borne genes mcr-1 to mcr-9 or to alteration of the pmr and pho operons (deletions, insertions or substitutions), but was conferred by an insertion sequence 1 (IS 1 )-induced total deletion of mgrB . Conclusion: This is the first reported whole-genome sequence of an unusual CoRKp isolate containing an IS 1 -induced deletion of mgrB .