WGS of K.leb from 103 Hospital
Materials and MethodsBacterial Isolate and Clinical Metadata The Klebsiella pneumoniae strain was isolated from a blood culture of a patient diagnosed with septicemia at Military Medical Hospital 103 (Hanoi, Vietnam) in July 2025. Primary phenotypic identification and antimicrobial susceptibility testing were performed using the VITEK-2 compact system (bioMrieux, Marcy-l'toile, France) at the hospital's microbiology department. Library Preparation and Whole Genome Sequencing Genomic DNA was extracted using the QIAamp DNA Mini Kit (Qiagen, Germany). The sequencing library was constructed using the Illumina DNA Prep kit. Whole-genome sequencing was conducted on an Illumina platform utilizing a 150 bp paired-end (x2) configuration to ensure high-fidelity data for Multi-Locus Sequence Typing (MLST).Bioinformatics Analysis and Novel ST Designation Raw reads were quality-filtered and de novo assembled using SPAdes v3.15.5 (careful mode), followed by a 500 bp length-filtering threshold for the resulting contigs. Species identity was genomically re-confirmed via KmerFinder 3.2 (CGE).Multi-Locus Sequence Typing (MLST) was performed by analyzing the seven standard housekeeping genes (gapA, infB, mdh, pgi, phoE, rpoB, and tonB). Although all seven loci matched previously known alleles in the BIGSdb-Pasteur database, their specific combination had not been documented. This novel allelic profile was submitted to and officially designated as a new Sequence Type (ST) by the Pasteur Institute curator, marking a distinct genetic lineage identified in the 2025 clinical surveillance in Vietnam.