Antimicrobial Susceptibility and Molecular Features of Colonizing Isolates of Pseudomonas aeruginosa and the Report of a Novel Sequence Type (ST) 3910 from Thailand

Abstract

Pseudomonas aeruginosa is an important pathogen as it can cause hospital-acquired infections. Additionally, it can also colonize in patients and in other various environments. Hence, this study aimed to investigate the antimicrobial susceptibility, and to study the molecular features, of colonizing isolates of P. aeruginosa from Songklanagarind Hospital, Thailand. Genomic DNA extraction, whole-genome sequencing (WGS), and bioinformatics analysis were performed in all studied isolates. The findings demonstrated that the majority of isolates were non-susceptible to colistin and carbapenem. For in silico study, multilocus sequence typing (MLST) revealed one novel sequence type (ST) 3910 and multiple defined STs. The isolates carried several antimicrobial resistance genes (blaOXA-50, aph(3′)-IIb, etc.) and virulence-associated genes (fleN, waaA, etc.). CRISPR-Cas sequences with different spacers and integrated bacteriophage sequences were also identified in these isolates. Very high SNPs were found in the alignments of the novel ST-3910 isolate with other isolates. A comparative genomic analysis exhibited phylogenetic clustering of our colonizing isolates with clinical isolates from many countries. Interestingly, ST-3981, ST-3982, ST-3983, ST-3984, ST-3985, ST-3986, ST-3986, ST-3986, ST-3987, and ST-3988, the new STs from published genomes, were assigned in this study. In conclusion, this WGS data might be useful for tracking the spread of P. aeruginosa colonizing isolates.

Nucleus-forming jumbophage PhiKZ therapeutically outcompetes non-nucleus-forming jumbophage Callisto

“…To further explore the potential of phage Callisto for medical and biotechnological applications, we tested the host spectrum, investigated the efficiency of plating (EOP) of the phage against lab strains and clinical strains of Pseudomonas spp. 41 , 42 and examined the presence of unwanted genes in the phage genome associated with bacterial virulence, antibiotic resistance, and the lysogenic life cycle that are disadvantageous for phage therapy. The results revealed that phage Callisto had a relatively broad host range compared to phage PhiKZ, 41 as indicated by its potential to form a clear zone in approximately half of the Pseudomonas spp.…”

Genomic Characterization of Multidrug-Resistant Enterobacteriaceae Clinical Isolates from Southern Thailand Hospitals: Unraveling Antimicrobial Resistance and Virulence Mechanisms

“…This study is part of a short-term surveillance effort conducted in ICU patients from five different hospitals in Southern Thailand over a 6-month period in 2019 [ 34 , 35 , 36 ]. The project identified 241 Enterobacteriaceae suspected of being resistant to carbapenem antimicrobials, all screened for resistance using MacConkey agar supplemented with 2 µg/mL of imipenem.…”