정석훈

Carbapenem-resistant <i>Pseudomonas aeruginosa</i> is one of the major concerns in clinical settings impelling a great challenge to antimicrobial therapy for patients with infections caused by the pathogen. While membrane permeability, together with derepression of the intrinsic beta-lactamase gene, is the global prevailing mechanism of carbapenem resistance in <i>P. aeruginosa</i>, the acquired genes for carbapenemases need special attention because horizontal gene transfer through mobile genet

To determine the prevalence and genotypes of extended-spectrum beta-lactamases (ESBLs) among clinical isolates of Klebsiella pneumoniae and Escherichia coli, we performed antibiotic susceptibility testing, pI determination, induction testing, transconjugation, and DNA sequencing analysis. Among the 509 isolates collected from 13 university hospitals in Korea, 39.2% produced ESBLs. ESBL-producing isolates were detected in every region in Korea. A total of 44.6% of the isolates produced both TEM-

Among 53 Acinetobacter baumannii isolates collected in 2004, nine imipenem-resistant isolates were obtained from clinical specimens taken from patients hospitalized in Busan, Korea. Nine carbapenemase-producing isolates were further investigated in order to determine the mechanisms underlying resistance. These isolates were then analyzed via antibiotic susceptibility testing, microbiological tests of carbapenemase activity, pI determination, transconjugation test, enterobacterial repetitive cons

The bla(CTX-M-14) gene was probably mobilized by IncF plasmids, which can readily spread in E. coli, causing horizontal dissemination of the resistance gene in Korea.

We report the first description of a new integron containing bla(VIM-2), a metallo-beta-lactamase gene from Enterobacter cloacae KU680, which was isolated from peritoneal fluid of a liver cirrhosis patient in South Korea. Antibiotic susceptibility testing, and modified Hodge and EDTA-disc synergy tests, were carried out to screen for metallo-beta-lactamase-producing strains. PCR and sequence analysis were used to identify and analyse the bla(VIM-2)-containing integron. The isolate was resistant

Species identification by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a routine diagnostic process for infectious diseases in current clinical settings. The rapid, low-cost, and simple to conduct methodology is expanding its application in clinical microbiology laboratories to diagnose the antimicrobial resistance (AMR) in microorganisms. Primarily, antimicrobial susceptibility testing is able to be carried out either by comparing the area

Despite decades' effort searching for the risk factors for E. coli BSI, systemic understanding covering the entire tripartite component is still lacking. This study detailed the organic impact of host-pathogen-treatment tripartite components for early mortality in patients with E. coli BSI.

The dissemination of Tn2006 was facilitated by its capability for intercellular transfer and that of Tn2009 was attributable to successful dissemination of the ST191 bacterial host carrying the transposon. Tn2008 was infrequent because of its insufficient ability to undergo intercellular transfer and the scarce bacterial host A. baumannii ST208. Gene amplification is an adaptive mechanism for bacteria that encounter antimicrobial drugs.

This study was carried out to investigate the epidemiological time-course of New Delhi metallo-beta-lactamase- (NDM-) mediated carbapenem resistance in Enterobacteriaceae in South Korea. A total of 146 non-duplicate NDM-producing Enterobacteriaceae recovered between 2010 and 2015 were voluntarily collected from 33 general hospitals and confirmed by PCR. The species were identified by sequences of the 16S rDNA. Antimicrobial susceptibility was determined either by the disk diffusion method or by

Klebsiella pneumoniae clinical isolates producing extended-spectrum β-lactamases (ESBLs; TEM and SHV types) are frequently implicated in hospital outbreaks. There are also reports of K. pneumoniae isolates producing various non-TEM, non-SHV ESBLs: CTX-M and GES/IBC types (1). Presently, the different GES-type ESBLs are designated by identical names (8). To clarify the misleading nomenclature of GES-type ESBLs, we propose maintaining the current denomination concerning the fully characterized GES

We investigated an outbreak caused by carbapenem-resistant Acinetobacter baumannii carrying the bla(OXA-23) gene. A novel insertion sequence (IS), named ISAba10, was found to be inserted into the ISAba1 element preceding the bla(OXA-23) gene in a group of isolates showing higher carbapenem MICs. The presence of ISAba10 was associated with increased OXA-23 expression, likely by providing additional promoter sequences. ISAba10 was also inserted into the carO outer membrane protein gene in most of