A5000952015- Antibiotic Resistance in Bacteria
- Bacterial Identification and Susceptibility Testing
- Antimicrobial Resistance in Staphylococcus
- Bacterial Genetics and Biotechnology
- Pharmaceutical and Antibiotic Environmental Impacts
- Antibiotics Pharmacokinetics and Efficacy
- Bacterial biofilms and quorum sensing
- Antibiotic Use and Resistance
- Enterobacteriaceae and Cronobacter Research
- Vibrio bacteria research studies
- Escherichia coli research studies
- Tuberculosis Research and Epidemiology
- RNA and protein synthesis mechanisms
- Genomics and Phylogenetic Studies
- Mycobacterium research and diagnosis
- Urinary Tract Infections Management
- Streptococcal Infections and Treatments
- Bacteriophages and microbial interactions
- Gut microbiota and health
- Plant Pathogenic Bacteria Studies
- Clostridium difficile and Clostridium perfringens research
- Infectious Diseases and Mycology
- Education and Learning Interventions
- Pneumonia and Respiratory Infections
- Education, Safety, and Science Studies
Korea Disease Control and Prevention Agency
2021-2024
Korea National Institute of Health
2022-2024
Yonsei University
2016-2023
Samsung Medical Center
2023
Sungkyunkwan University
2023
Chosun University
2021
Institut Pasteur
2013-2016
Seoul National University
2006-2011
Ewha Womans University
2010
Pepose Vision Institute
2007
Bacterial genomics has greatly expanded our understanding of microdiversification patterns within a species, but analyses at higher taxonomical levels are necessary to understand and predict the independent rise pathogens in genus. We have sampled, sequenced, assessed diversity genomes validly named tentative species Acinetobacter genus, clade including major nosocomial biotechnologically important species. inferred robust global phylogeny delimited several new putative The genus is very...
Increased expression of chromosomal genes for resistance-nodulation-cell division (RND)-type efflux systems plays a major role in the multidrug resistance (MDR) Acinetobacter baumannii. However, relative contributions three most prevalent pumps, AdeABC, AdeFGH, and AdeIJK, have not been evaluated clinical settings. We screened 14 MDR isolates shown to be distinct on basis multilocus sequence typing (MLST) pulsed-field gel electrophoresis (PFGE) presence overexpression Ade analyzed sequences...
Acinetobacter baumannii is a nosocomial pathogen of increasing importance due to its multiple resistance antibiotics and ability survive in the hospital environment linked capacity form biofilms. To fully characterize contribution AdeABC, AdeFGH, AdeIJK resistance-nodulation-cell division (RND)-type efflux systems acquired intrinsic resistance, we constructed, from an entirely sequenced susceptible A. strain, set isogenic mutants overexpressing each system following introduction point...
Background. Colistin resistance is of concern since it increasingly needed to treat infections caused by bacteria resistant all other antibiotics and has been associated with poorer outcomes. Longitudinal data from in vivo series are sparse. Methods. Under a quality-improvement directive intensify infection-control measures, extremely drug-resistant (XDR) undergo phenotypic molecular analysis. Results. Twenty-eight XDR Acinetobacter baumannii isolates were longitudinally recovered during...
To monitor national antimicrobial resistance (AMR), the Korea Global AMR Surveillance System (Kor-GLASS) was established. This study analyzed bloodstream infection (BSI) cases from Kor-GLASS phase I January 2017 to December 2019. Nine non-duplicated target pathogens, including Staphylococcus aureus, Enterococcus faecalis, faecium, Streptococcus pneumoniae, Escherichia coli, Klebsiella Pseudomonas aeruginosa, Acinetobacter spp., and Salmonella were isolated blood specimens eight sentinel...
Overexpression of chromosomal resistance-nodulation-cell division (RND)-type efflux systems with broad substrate specificity contributes to multidrug resistance (MDR) in Acinetobacter baumannii We have shown that modulation expression the structural genes for AdeABC and AdeIJK confers MDR results numerous alterations membrane-associated cellular functions, particular biofilm formation. However, contribution these RND pumps cell fitness virulence has not yet been studied. The biological cost...
The Korean government established an antimicrobial resistance (AMR) surveillance system, compatible with the Global AMR Surveillance System (GLASS): Kor-GLASS. We describe results from first year of operation Kor-GLASS May 2016 to April 2017, comprising all non-duplicated clinical isolates major pathogens blood, urine, faeces and urethral cervical swabs six sentinel hospitals. Antimicrobial susceptibility tests were carried out by disk diffusion, Etest, broth microdilution agar dilution...
ABSTRACT Gene amplification is believed to play an important role in antibiotic resistance but has been rarely documented clinical settings because of its unstable nature. We report a rise MICs from 0.5 16 μg/ml successive Acinetobacter baumannii isolated over 4 days patient being treated with tobramycin for infection by multidrug-resistant A. , resulting therapeutic failure. Isolates were characterized whole-genome sequencing, real-time and reverse transcriptase PCR, growth assays determine...
A total of 431 Pseudomonas aeruginosa clinical isolates were collected from 29 general hospitals in South Korea 2015. Antimicrobial susceptibility was tested by the disk diffusion method, and MICs carbapenems determined agar dilution method. Carbapenemase genes amplified PCR sequenced, structures class 1 integrons surrounding carbapenemase gene cassettes analyzed mapping. Multilocus sequence typing (MLST) pulsed-field gel electrophoresis (PFGE) performed for strain typing. Whole-genome...
To investigate the risk factors of patients with Klebsiella pneumoniae (KP) bloodstream infection (BSI) a focus on antimicrobial resistance and virulence factors. All KP BSI (n = 579) from six general hospitals during 1 year period were included in this study. The hosts causative isolates assessed to determine associations 30 day mortality by multivariate Cox hazards modelling. rate was 16.9% (98/579). Among host-associated factors, increased SOFA score leucopenia status exhibited strong...
Here, we aimed to elucidate the differences in microbiota composition between patients with gout and those asymptomatic hyperuricemia (asHU) determine effect of uric acid-lowering therapy (ULT) on gut microbiome.Stool samples from asHU (n=8) three groups patients, i.e., acute before ULT (0ULT, n=14), same after 30-day (30ULT, n=9), chronic ≥6-month (cULT, n=18) were collected analyzed using 16S rRNA gene-based pyrosequencing. The microbial taxonomy communities, species diversity,...
To assess the epidemiology of carbapenemase-producing Enterobacteriaceae (CPE) in South Korea.From 2011 to 2015, 2487 carbapenem-nonsusceptible were collected through Korean National Laboratory Surveillance System. Disk-diffusion for antimicrobial susceptibility, PCR/sequencing detect carbapenemase genes and multilocus sequence typing molecular carried out.The number was increasing approximately 1.5-fold per year proportion CPEs exponentially confirmed from 2014. KPC most dominant, mostly...
ABSTRACT The amikacin resistance gene aphA6 was first detected in the nosocomial pathogen Acinetobacter baumannii and subsequently other genera. Analysis of 133 whole-genome sequences covering taxonomic diversity spp. chromosome 2 isolates A. guillouiae , which is an environmental species, 1 8 parvus isolates, 5 34 isolates. also present 29 out 36 screened by PCR, indicating that it ancestral to this species. P native promoter for replaced generated use insertion sequence IS Aba125 brought a...
High rates of carbapenem resistance in the human pathogen Acinetobacter baumannii threaten public health and need to be scrutinized.A total 356 A. 50 non-baumannii spp. (NBA) strains collected 2013 throughout South Korea were studied. The type blaOXA-23 transposon was determined by PCR mapping molecular epidemiology assessed MLST. Twelve representative two comparative entirely sequenced single-molecule real-time sequencing.The rate 88% baumannii, mainly due blaOXA-23, with five exceptional...
Surveillance plays a pivotal role in overcoming antimicrobial resistance (AMR) bacterial pathogens, and variety of surveillance systems have been set up employed many countries. In 2015, the World Health Organization launched Global Antimicrobial Resistance System (GLASS) as part global action plan to enhance national research. The aims GLASS are foster development enable collection, analysis sharing standardised, comparable validated data on AMR between different South Korean system,...
ABSTRACT Translational attenuation has been proposed to be the mechanism by which erm (B) gene is induced. Here, we report genetic and biochemical evidence, obtained using erythromycin as inducing antibiotic, that supports this hypothesis. We also show increases level of transcript stalling ribosome on leader mRNA thereby facilitating stabilization processing mRNA. Erythromycin-induced were observed with an ochre stop at codons 11 13 but not codon 10. This suggests does stall before reaches...
In Gram-negative bacteria, acquired 16S rRNA methyltransferases ArmA and NpmA confer high-level resistance to all clinically useful aminoglycosides by modifying, respectively, G1405 A1408 in the A-site. These enzymes must coexist with several endogenous that are essential for fine-tuning of decoding center, such as RsmH RsmI Escherichia coli , which methylate C1402 RsmF C1407. The have a contrasting distribution—ArmA has spread worldwide, whereas single clinical isolate producing been...
A total of 281 nonduplicated Staphylococcus aureus blood isolates were collected from January to May 2017 eight hospitals in South Korea investigate the epidemiological traits ceftaroline resistance methicillin-resistant S. (MRSA). Cefoxitin-disk diffusion tests and mecA gene PCR revealed that 56.6% (159/281) MRSA, most belonged ST5 (50.3%, 80/281) ST72 (41.5%, 66/281). Of MRSA isolates, 44.0% (70/159) nonsusceptible (MIC ≥ 2 mg/liter), whereas all methicillin-susceptible susceptible drug....
A MALDI-TOF MS-based identification method for KPC-producing Enterobacterales was developed.The molecular mass of the intact KPC-2 polypeptide estimated blaKPC-2 transformants using MALDI Microflex and exact confirmed by LC a high-resolution MS/MS system. total 1181 clinical strains, including 369 KPC producers 812 non-producers, were used to set up methodology results compared with those from PCR analyses. For external validation, 458 isolates general hospital between December 2018 April...
Resistance to β-lactams in Acinetobacter baumannii involves various mechanisms. To decipher them, whole genome sequencing (WGS) and real-time quantitative polymerase chain reaction (RT-qPCR) were complemented by mass spectrometry (MS) selected monitoring mode (SRM) 39 clinical isolates. The targeted label-free proteomic approach enabled, one hour using a single method, the detection of 16 proteins associated with antibiotic resistance: eight acquired β-lactamases (i.e. GES, NDM-1, OXA-23,...