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bioRxiv · 10.1101/2024.11.27.625610

Genomic characterization and functional insights of multidrug-resistant Klebsiella pneumoniae strain BCSIR-JUMIID

Abstract

Klebsiella pneumoniae is a prominent opportunistic pathogen associated with multidrug resistance (MDR) and high morbidity and mortality rates in healthcare settings. The emergence of strains resistant to last-resort antibiotics, such as colistin and carbapenems, poses significant therapeutic challenges. This study presents the complete genome analysis of the MDR strain K. pneumoniae BCSIR-JUMIID to elucidate its genetic architecture, resistance mechanisms, and virulence factors. The genome of K. pneumoniae BCSIR-JUMIID, isolated from a pharmaceutical wastewater in Dhaka, Bangladesh, was sequenced using next-generation sequencing technologies. Bioinformatics tools were employed for genome assembly, annotation, and functional analysis. Phylogenetic relationships were established through whole-genome comparisons. Antibiotic resistance genes, virulence factors, and mobile genetic elements were identified using the Comprehensive Antibiotic Resistance Database (CARD), ResFinder-4.5.0, Virulence Factors Database (VFDB), and various phage identification tools. The genome of K. pneumoniae BCSIR-JUMIID consists of 5,769,218 bp with a G+C content of 56.79%, assembled into 343 contigs. A total of 6,062 coding sequences (CDS), including 1,087 hypothetical proteins, 49 tRNA genes, and 4 rRNA genes, were identified. Key loci involved in capsular polysaccharide and O-antigen biosynthesis (KL150, KL107-D1, O3b) were detected. A diverse array of antibiotic resistance genes was uncovered, including those conferring resistance to beta-lactams, quinolones, and colistin. Phage analysis revealed the presence of multiple dsDNA bacteriophages, and CRISPR-Cas systems indicated robust phage defense mechanisms. The genomic analysis of K. pneumoniae BCSIR-JUMIID provides a detailed understanding of its resistance and virulence mechanisms, highlighting its potential for horizontal gene transfer and rapid adaptation. These findings underscore the necessity for continued surveillance and novel therapeutic strategies to combat MDR K. pneumoniae infections effectively.

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BibTeXRIS

Ahmed, M. F., Faruk, M. O., Sarkar, M. M. H., Hossain, M. I., Shabuj, A. A.-M., Bhim, M., Mehzabin, K., Chowdhury, S. F., Naser, S. R., Mumtaz, T.. 2024-11-28. Genomic characterization and functional insights of multidrug-resistant Klebsiella pneumoniae strain BCSIR-JUMIID. https://doi.org/10.1101/2024.11.27.625610

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