• Journal of Microbiology
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• 제43권5호
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• pp.443-450
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• 2005

The multi-host pathogen, Pseudomonas aeruginosa, possesses an extraordinary versatility which makes it capable of surviving the adverse conditions provided by environmental, host, and, presumably, competing microbial factors in its natural habitats. Here, we investigated the P. aeruginosa-Bacillus subtilis interaction in laboratory conditions and found that some P. aeruginosa strains can outcompete B. subtilis in mixed planktonic cultures. This is accompanied by the loss of B. subtilis viability. The bactericidal activity of P. aeruginosa is measured on B. subtilis plate cultures. The bactericidal activity is attenuated in pqsA, mvfR, lasR, pilB, gacA, dsbA, rpoS, and phnAB mutants. These results suggest that P. aeruginosa utilizes a subset of conserved virulence pathways in order to survive the conditions provided by its bacterial neighbors.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 추계국제학술대회
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• pp.3-13
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• 2020

Pseudomonas aeruginosa is a ubiquitous gram-negative bacterium causing serious infections. The P. aeruginosa T3SS is a syringe-like apparatus on the bacterial surface, with 4 effector toxins: ExoS, ExoT, ExoY, and ExoU. Here, we investigated the effect of ExoS and ExoT of the T3SS of P. aeruginosa K strain (PAK). The type three secretion system (T3SS) is a major virulence system of Pseudomonas aeruginosa (P. aeruginosa). The effector protein Exotoxin S (ExoS) produced by P. aeruginosa is secreted into the host cells via the T3SS. For the purpose of screening the inhibitors with regard to ExoS secretion, we developed the sandwich-type enzyme-linked immunosorbent assay (ELISA) system. PAK clinical strains induce proinflammatory cytokine production through the T3SS, and this involves NF-κB activation in pneumonia mouse models. We tried to confirm the role of the NF-κB transcription factor in ExoS- and ExoT-induced pneumonia mouse models. pro-inflammatory cytokines induction in response to ExoS and ExoT infection relied on NF-κB activation. Our findings highlight the roles of natural poduct in inhibiting proinflammatory cytokine expression during ExoS and ExoT exposure in PAK infections, paving the way for a novel therapeutic approach for the treatment of pulmonary infections.

• KSBB Journal
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• 제26권1호
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• pp.19-26
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• 2011

Of the 500 Actinomycetes isolates obtained from soil, one isolate grown on maltose as the sole carbon source produced compound BHK-P19, which inhibited the growth of multiple drug resistant P. aeruginosa 0245. Ultraviolet radiation mutagenesis curtailed production of BHK-P19. Mutation of the BHK-P19 producer using N-methyl-N'-nitro-N-nitroso-guanidine obviated the antibacterial activity to P. aeruginosa 0245, but not towards P. aeruginosa 0225. The mixing of BHK-P19 and BHK-S5 culture extracts inhibited P. aeruginosa 0254, 0225 and 1113. The combined application of BHK-P19 culture extract and Schizandra chinensis Baillon extract inhibited P. aeruginosa 0254, 0225, 0826, 1113, 1378, 1731 and 2492. Use of various concentrations of BHK-P19 culture extract and ampicillin markedly increased antibacterial activity against multi-drug resistant P. aeruginose 1113.

• 대한임상검사과학회지
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• 제43권2호
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• pp.68-74
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• 2011

Pseudomonas aeruginosa is an aerobic, Gram-negative, glucose-nonfermenting bacterium, which has emerged as a serious opportunistic pathogen. Recently, outbreaks of carbapenem resistant P. aeruginosa give rise to significant therapeutic challenges for treating nosocomial infections. The genes of metallo-${\beta}$-lactamase (MBL), a powerful carbapenemase, are carried as a part of the mobile gene cassettes inserted into integrons playing an important role in rapid dissemination of antibiotic resistance genes among bacterial isolates. In this study, we investigated the prevalence of integron in imipenem resistant P. aeruginosa isolates. A total of 61 consecutive, non-duplicate, and imipenem resistant P. aeruginosa strains were isolated from a university hospital in the Chungcheong province of Korea. We employed repetitive extragenic palindromic sequence-based PCR (rep-PCR) method for the selection of clonally different P. aerusinosa strains. PCR and DNA sequencing were conducted for the detection of integrons. Twenty-one clonally different P. aeruginosa strains were isolated. Only one (P28) of the strains harbored $bla_{VIM-2}$ that was found as gene cassettes in class 1 integrons. Four of 21 carbapenem resistant P. aeruginosa strains harbored class 1 integron containing aminoglycoside resistance determinant. All of the integrons detected in the study contained more than one resistance gene cassette, which can mediate resistance to multiple antibiotics. To prevent further spreading of the multi-drug resistant P. aeruginosa, conseguent monitoring and clinical polices are required.

• Archives of Plastic Surgery
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• 제34권5호
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• pp.551-556
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• 2007

Purpose: Pseudomonas aeruginosa is an etiologic agent in serious wound infection. Pseudomonas aeruginosa infection is problematic because this organism is resistant to many antimicrobial drugs. The purpose of this study was to compare the bactericidal effect of commonly used topical agents and their effect on wound healing. Methods: Pseudomonas aeruginosa-infected full-thickness skin defect was developed on the mouse to compare 3 commonly used topical agents-Betadine, 2% Gentamicin solution and 0.3% Acetic acid with the control group. Wound size change, bacterial colony counts and histologic findings of each groups were analyzed. Results: The wound size decreased in all treated groups as compared with the control group. However, there was no statistical difference. Gentamicin solution group was showed the lowest bacterial colony count and statistically significant difference compared with the control group(p=0.032). Other treated groups were also effective against Pseudomonas aeruginosa, but not different statistically. Histologic findings revealed that epithelialization, granulation tissue formation and microvessel proliferation were increased and necrosis and inflammation were decreased in all treated groups compared to the control group, but not different statistically. Betadine group significantly increased granulation tissue formation compared to the control group (p= 0.041). Conclusion: There is no universal topical agent that enhances most aspects of wound healing while simultaneously decreasing the bacterial concentration. However, Gentamicin solution may be an optimal topical agent for Pseudomonas aeruginosa infected wound. Further study should experiment on human with Gentamicin solution to confirm a effect on Pseudomonas aeruginosa infected wound for clinical applications.

• Tuberculosis and Respiratory Diseases
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• 제77권4호
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• pp.172-177
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• 2014

Background: Pseudomonas aeruginosa infection is particularly associated with progressive and ultimately chronic recurrent respiratory infections in chronic obstructive pulmonary disease, bronchiectasis, chronic destroyed lung disease, and cystic fibrosis. Its treatment is also very complex because of drug resistance and recurrence. Methods: Forty eight cultures from 18 patients with recurrent P. aeruginosa pneumonia from 1998 to 2002 were included in this study. Two or more pairs of sputum cultures were performed during 2 or more different periods of recurrences. The comparison of strains was made according to the phenotypic patterns of antibiotic resistance and chromosomal fingerprinting by pulsed field gel electrophoresis (PFGE) using the genomic DNA of P. aeruginosa from the sputum culture. Results: Phenotypic patterns of antibiotic resistance of P. aeruginosa were not correlated with their prior antibiotic exposition. Fifteen of 18 patients (83.3%) had recurrent P. aeruginosa pneumonia caused by the strains with same PFGE pattern. Conclusion: These data suggest that the most of the recurrent P. aeruginosa infections in chronic lung disease occurred due to the relapse of prior infections. Further investigations should be performed for assessing the molecular mechanisms of the persistent colonization and for determining how to eradicate clonal persistence of P. aeruginosa.

• 대한임상검사과학회지
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• 제40권2호
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• pp.75-79
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• 2008

86 clinical isolates of Acinetobacter baumannii and 116 clinical isolates of Pseudomonas aeruginosa strains isolated from clinical specimens were collected from a hospital in Daegu city area. We investigated the Antimicrobial susceptibility patterns of A. baumannii and P. aeruginosa isolated from sputum, urine, wound, blood, nasal swab, body fluid. The antimicrobial resistance of A. baumannii were shown 96% for piperacillin, carbenicillin 82%. cefotaxime 78%, ciprofloxacin 77%, sulfamethoxazole/trimethoprime 76%, ceftazidime 75%, tobramycin 72%. For P. aeruginosa, the resistance of cefotaxime and sulfamethoxazole/trimethoprime were 100%, carbenicillin 49%, piperacillin 47%, ticarcillin 45%, ticarcillin/ clavulanic acid 40%.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2002년도 봄 학술발표대회 발표논문집
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• pp.445-447
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• 2002

본 연구는 환경친화적인 biosurfactant를 생산하는 Pseudomonas aeruginosa EMS1 and KH7를 rhamnolipid의 rhlR, rhlA, rhlB를 기초로한 primer를 이용하여 752bp, 802pb, 1280bp pcr을 수행하였으며 $pGEM^{(R)}$ / - T Easy Vector gene cloning 하여 Pseudomonas aeruginosa EMS1 and KH7의 Partial Sequencing를 서로 비교하였다. 이들 실험을 통하여 Pseudomonas aeruginosa의 유전적 구조 및 특성을 비교하여 유전적 조작을 위한 기초적인 자료가 되도록 한다.

• 한국미생물·생명공학회지
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• 제29권3호
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• pp.127-133
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• 2001

냉각탑수 중의 Legionella 속 균을 저감시킬 수있는 방법개발의 일환으로 L. pneumophila에 강한 항균성물질을 생산하는P. seruginosa KLP-2 균주를 냉각탑수로부터 분리 동정하였다 P.aeruginosa KLP-2 균주를 냉각탑수로부터 분리 동정하였다. P. aeruginosa KLP-2 균주의 배양여액은 L. pneumophila의 Vibro cholerae non-Ol Bacillus cereus, Bacillus subtilis 및 Staphylococcus aureus에 대해서도 항균성을 나타내었다. P. seruginosa KLP-2 균주 배양여액의 항균활성을 증가시키기 위한 최적조건은 0.1%의 $K_2$$HPO_4$와 0.05%의 $MgSO_4$$7H_2$O로 조성되 무기염배지에 탄소원으로써 1%의 glycerol, 질소원으로써, 0.6%의 proteose peptone이 첨가된 pH 7.0의 배지 조건에서 가장 높은 항균 활성을 나타내었으며 $35^{\circ}C$에서 20시간 진탕배양(50 rpm)한 후 4일간 정치 배양하였을 때 최대의 항균활성을 나타내었다.

• 대한수의학회지
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• 제61권2호
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• pp.16.1-16.6
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• 2021

Pseudomonas aeruginosa is one of the most common pathogenic species associated with canine otitis externa (OE). Their resilience is achieved by forming a biofilm, which allows these bacteria to evade even the harshest of treatments. This study evaluated the in vitro synergistic efficacy of N-acetylcysteine (NAC) with different antimicrobial agents against P. aeruginosa isolated from dogs with OE to develop an effective treatment against P. aeruginosa. The antimicrobial activity was evaluated by the minimum inhibitory concentration test using the microdilution method. The efficacy of antibiofilm formation was evaluated using a crystal violet stain method. The treatment solutions included NAC alone, and in synergy with enrofloxacin, polymyxin B, and gentamicin. NAC alone exhibited antimicrobial and antibiofilm abilities. On the other hand, the combination of NAC and the antibiotics did not show any significant synergistic effects against P. aeruginosa.