• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.167-177
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• 2007

From the total 121,294 clinical materials submitted to the Department of Laboratory Medicine of "C" hospital from December 1, 2004 to November 30, 2006, 3,408 Pseudomonas spp. were isolated. The isolation frequencies of Pseudomonas spp. were as follows, P. aeruginosa 95.5%, P. putida 2.5%, P. fluorescens 0.8%, along with low frequencies of P. luteola, P. alcaligenes, P. stutzeri, P. oryzihabitants, P. mendocina and unidentified Pseudomonas species. The isolation rates of Pseudomonas spp. according to season and sex were evenly distributed. The isolated frequency of Pseudomonas spp. in male was two times higher than that of in female showing significantly more male patients in surgical areas and more female patients in internal areas (p<0.001). In monthly analysis, Pseudomonas spp. were the most frequently isolated in July (10.4%), but lowest in February (5.6%). Half of Pseudomonas spp. were isolated from sputum (48.2%). In the susceptibility analysis of Pseudomonas spp. by VITEK II AST cards, the Pseudomonas spp showing higher susceptibility against antimicrobial agents were piperacillin/tazobactam (82.7%) in P. aeruginosa; amikacin (84.7%), colistin (83.3%) in P. putida; and amikacin (96.3%), cefepime (87.5%), ceftazidime (87.5%) ciprofloxacin (92.3%), colistin (88.5%) gentamicin (96.2%), isepamicin (96,1%), meropenem (92.3%), netilmicin (96.0%), piperacillin/ tazobactam (95.4%) and tobramycin (92.6%) in P. fluorescens.

• Korean Journal of Microbiology
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• v.24 no.3
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• pp.302-307
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• 1986

In order to investigate the properties of cephalospornase, a strong antibiotic resistant strain(H 112) was isolated from Pseudomonas aeruginose. The extracted enzyme had the following characteristics. Optimum temperature was 45.deg.C and unstable over $55^{\circ}C$, and optimum pH was 8.5. Cephalosporinase activity was not inhibited by metal ions such as $Mn^{++},\;Cu^{++}\;Fe^{++},\;Fe^{+++}$, and EDTA. But it was inhibited by some antibiotics such as carbenicillin, cefoxitin, cefotaxime, cefamandole, cefoperazone and SDS. The Vmax values of the enzyme were 100 at cephaloridine and 2.8 at cefoperazone, respectively. The molecular weight of cephalosporinase was estimated to be about $37.500{\pm}3,000$ by high performance liquid chromatography and nitrocefin reaction.

• Biomedical Science Letters
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• v.18 no.1
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• pp.16-21
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• 2012

Although there are many potential cytotoxic molecules released from bacteria, the role of these molecules on the apoptosis of various cancer cells is not well understood. Pseudomonas aeruginosa (P. aeruginosa) is a Gram-negative, aerobic and rod-shaped bacterium, and has a number of virulence factors. To understand the cytotoxic effect of bacterial extracts on the colorectal cancer cell line, HCT 116 cells, we examined alteration of the cell viability, proliferation, cell cycle and apoptosis of HCT 116 cells after treatment with extract of P. aeruginosa (PaE). These cytotoxicity of PaE occurred in a time- and a dose-dependent manners. In addition, PaE arrested the cell cycle of HCT 116 cell in a time-dependent manner. PaE inhibited the protein levels of Bcl-2 and induced the release of cytochrome c from mitochondria of HCT 116 cells. The decrease of procaspase-3 was induced by the treatment of PaE. These results indicate that PaE has a cytotoxicity in HCT 116 cells via the induction of apoptosis associated with mitochondrial pathway. Therefore, PaE may used as the potential target for the treatment of colorectal cancer.

• Journal of Pharmacopuncture
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• v.25 no.1
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• pp.37-45
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• 2022

Objectives: The quorum-sensing-inhibitory and anti-biofilm activities of the methanol extract of E. globulus leaves were determined against clinically isolated multidrug-resistant Pseudomonas aeruginosa. Methods: The preliminary anti-quorum-sensing (AQS) activity of eucalyptus was investigated against a biosensor strain Chromobacterium violaceum ATCC 12472 (CV12472) by using the agar well diffusion method. The effect of sub-minimum inhibitory concentrations (sub-MICs) of the methanol extract of eucalyptus on different quorum-sensing-regulated virulence factors, such as swarming motility, pyocyanin pigment, exopolysaccharide (EPS), and biofilm formation, against clinical isolates (CIs 2, 3, and 4) and reference PA01 of Pseudomonas aeruginosa were determined using the swarm diameter (mm)-measurement method, chloroform extraction method, phenol (5%)-sulphuric acid (concentrated) method, and the microtiter plate assay respectively, and the inhibition (%) in formation were calculated. Results: The preliminary AQS activity (violacein pigment inhibition) of eucalyptus was confirmed against Chromobacterium violaceum ATCC 12472 (CV12472). The eucalyptus extract also showed concentration-dependent inhibition (%) of swarming motility, pyocyanin pigment, EPS, and biofilm formation in different CIs and PA01 of P. aeruginosa. Conclusion: Our results revealed the effectiveness of the E. globulus extract for the regulation of quorum-sensing-dependent virulence factors and biofilm formation at a reduced dose (sub-MICs) and suggest that E. globulus may be a therapeutic agent for curing and controlling bacterial infection and thereby reducing the possibility of resistance development in pathogenic strains.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.371-376
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• 2002

A biosurfactant-producing bacterial strain was selected from diesel-contaminated soil by measuring the oil-film collapsing activity and identified as Pseudomonas aeruginosa D2D2. When glucose and olive oil were used as carbon sources, 11.46 g/1 of biosurfactant was obtained. Based on TLC analysis, the biosurfactant produced from P. aeruginosa D2D2 was identified as a glycolipid, consisting of two types of biosurfactants (Type I and Type II). The purified glycolipid reduced the surface tension of the culture from 72 dyne/cm to 27 dyne/cm. The hydrophilic and hydrophobic moiety of the biosurfactant were rhamnose and ${\beta}$-hydroxydecanoic acid, as determined by FAB-MS and NMR analyses, respectively.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1520-1526
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• 2009

We have identified the iscR (PA3815) gene encoding an iron-sulfur cluster assembly regulator homolog as one of the genes required for peroxide resistance in Pseudomonas aeruginosa PA14. Here, we present the phenotypic characterization of an iscR deletion mutant in terms of KatA expression, stress responses, and virulence. The iscR null mutant exhibited reduced KatA activity at the posttranslational level, hypersensitivity to hydrogen peroxide, and virulence-attenuation in Drosophila melanogaster and mouse peritonitis models. These phenotypes were fully restored by multicopy-based expression of katA. These results suggest that the requirement of IscR in P. aeruginosa is related to the proper activity of KatA, which is crucial for peroxide resistance and full virulence of this bacterium.

• Korean Journal of Microbiology
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• v.22 no.1
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• pp.29-34
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• 1984

238 strains of bacteria were isolated from sewage and soil samples collected mainly in Seoul and its suburbs by enrichment culture on crude oil or hydrocarbon minimal medium. Of the isolates, 68 strains were tentatively identified as the genus Pseudomonas, 11 strains as Alcaligenus, and 10 strains as Acinetobacter. Of the 68 strains of Pseudomonas sp., 35 strains were identified as P. aeruginosa, 5 strains as P. fluorescence, 10 strains as P. putida, and 2 strains as P. mendocina.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.4
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• pp.37-41
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• 2007

The aim of this study is to establish RGP lens care system using RGP lens multi-purpose solution(MPS) and cleaner. Each RGP lens was incubated in Pseudomonas aeruginosa standard strain, and the numbers of P. aeruginosa colony remaining after treatment by using MPS and/or cleaner including surface activating components were estimated. Soaking only in MPS for 30 min reduced the number of P. aeruginosa up to 50%. 95% of P. aeruginosa was eliminated at RGP lenses soaked in MPS for 4 hr, but P. aeruginosa was not detected at RGP lenses soaked for 6 hr. When only cleaner was used for RGP lens care, 70% of P. aeruginosa was eliminated. This result showed that using cleaner had more effective at removing P. aeruginosa than soaking in MPS for 30 min. When soaking in MPS for 30 min after using cleaner reduced the number of P. aeruginosa up to 36% of that which soaking only in MPS for 30 min. This result suggested that using cleaner could be helpful to improve the disinfection efficacy of short time soaking in MPS.

• KSBB Journal
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• v.15 no.1
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• pp.27-34
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• 2000

A marine bacterium having a high oil-degrading activity was isolated form the oil-polluted southern sea of Korea, and was identified as Pseudomonas aeruginosa and was named Pseudomonas aeruginosa BYK-2. The optimal tmeperatur, culture time, pH and NaCl concentration for biosurfactant production and cell growth showed $25^{\circ}C$, 48h, 7.0 and 0%(w/v), respectively. After cultivation at $25^{\circ}C$, 180 rpm in 250 mL erlenmeyer flask for 7days, 1%(w/v) arabian light crude oil and bunker C oil which are considered to be hardly degradable compounds were degraded 92.1%(w/w) and 76%(w/w) respectively. And then, cell adherence was measured on various carbon sources. The cell adherence indicated over 80% on hydrocarbons(arabian light crude oil, kuwait curde oil, bunker C oil, n-paraffine, n-hexadecane, n-tetradecane) as carbon sources. Lecithin among fatty acids(oleic acid, olive oil, lecithin) showed highest cell adherence of 91.5%. The cell adherence of sugars(arabinose, trehalose, dextrose, galactose, lactose, fructose, maltose, sorbitol, sucrose) observed to be less than 70% except for arabinose, galactose, sorbitol and sucrose.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.384-386
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• 2014

Pseudomonas aeruginosa is an opportunistic pathogen that inhabits various natural and artificial environments, such as pathogenesis, water, soil and air. They can cause serious problems, such as pathogenic infection. In this study, 220 colonies were isolated from water and soil environment that assumed to be P. aeruginosa using a membrane filter method based on International Organization for Standardization (ISO/NP 16266). Identification of the isolates was determined by physiobiochemical characteristics using newly modified ISO method which includes the resistance to 1,10 phenanthroline test. Only one of 220 presumed P. aeruginosa strains isolated from effluence water using a drain swab was determined as P. aeruginosa-positive by the ISO/NP 16266 method. Subsequently, the resistance to 1,10 phenanthroline test, which was newly proposed by ISO in 2014 and applied in this study, was considered as more precise and improvable method for identification of P. aeruginosa.