• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1539-1548
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• 2017

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen that commonly causes fatal infections in cystic fibrosis and burn patients as well as in patients who are hospitalized or have impaired immune systems. P. aeruginosa infections are difficult to treat owing to the high resistance of the pathogen to conventional antibiotics. Despite several efforts, no effective prophylactic vaccines against P. aeruginosa are currently available. In this study, we investigated the activity of the CIA06 adjuvant system, which is composed of alum and de-O-acylated lipooligosaccharide, on a P. aeruginosa outer membrane protein (OMP) antigen vaccine in mice. The results indicated that CIA06 significantly increased the antigen-specific IgG titers and opsonophagocytic activity of immune sera against P. aeruginosa. In addition, the antibodies induced by the CIA06-adjuvanted vaccine exhibited higher cross-reactivity with heterologous P. aeruginosa strains. Finally, mice immunized with the CIA06-adjuvanted vaccine were effectively protected from lethal P. aeruginosa challenge. Based on these data, we suggest that the CIA06 adjuvant system might be used to promote the immunogenicity and protective efficacy of the P. aeruginosa OMP vaccine.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.301-308
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• 2019

The emergence and spread of multidrug resistant (MDR) Pseudomonas aeruginosa is a critical problem worldwide. The pathogenesis of P. aeruginosa is due partly to the production of several cell-associated and extracellular virulence factors. This study examined the distribution of virulence factors and antimicrobial resistance patterns of carbapenem-resistant P. aeruginosa (CRPA) isolated from a tertiary hospital in Daejeon, Korea. Antimicrobial susceptibility testing was performed using the disk diffusion method, and PCR and DNA sequencing were performed to determine for the presence of virulence genes. In addition, the sequence type (ST) of MDR P. aeruginosa was investigated by multilocus sequence typing (MLST). Among 32 CRPA isolates, 14 (43.8%) were MDR and the major ST was ST235 (10 isolates, 71.4%). All isolates were positive for the presence of virulence genes and the most prevalent virulence genes were toxA, plcN, and phzM (100%). All isolates carried at least eight or more different virulence genes and nine (28.1%) isolates had 15 virulence genes. The presence of the exoU gene was detected in 71.4% of the MDR P. aeruginosa isolates. These results indicate that the presence of the exoU gene can be a predictive marker for the persistence of MDR P. aeruginosa isolates.

• Tuberculosis and Respiratory Diseases
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• v.77 no.4
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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.

• Natural Product Sciences
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• v.25 no.2
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• pp.172-180
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• 2019

Infections with Pseudomonas aeruginosa are difficult to treat not only because it is often associated with multidrug-resistant infections but also it is able to form biofilm. The aim of this study was to evaluate the antibiofilm and anti-Quorum Sensing (QS) activities of Thymbra capitata essential oils (EOs) against Beta Lactamase (BL) producing P. aeruginosa and the reference strain P. aeruginosa 10145. GC/MS analysis showed that thymol (23.25%) is the most dominant compound in T. capitata EOs. The MICs of T. capitata EOs against P. aeruginosa (BL) and P. aeruginosa 10145 were 1.11%. At sub MIC (0.041, 0.014 and 0.0046%), the EOs of T. capitata remarkably inhibited the biofilm formation of both strains tested and complete inhibition of the biofilm formation was reported at 0.041%. The EOs of T. capitata were found to inhibit the swarming motility, aggregation ability and hydrophobic ability of P. aeruginosa (BL) and P. aeruginosa 10145. Interestingly, the EOs of T. capitata reduce the production of three secreted virulence factors that regulated by QS system including pyocyanin, rhamnolipids and LasA protease. The potent antibiofilm and anti-QS activities of T. capitata EOs can propose it as a new antibacterial agent to control pseudomonas infections.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.244-245
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• 2001

산폐유의 농도를 l~8% 까지 단계별로 조정하여 P. aeruginosa EMS1과 mutant strain A34의 유화활성 및 생육도, 표면장력 등을 서로 비교하였다. P. aeruginosa의 경우 1%의 산폐유가 첨가되었을 때 유화활성이 가장 높았으며, 1~3%까지 유화활성이 높게 나타났으며, mutant strain의 경우 2%에서 가장 높은 유화활성 값을 나타내었고, 1~3%까지 유화활성이 높게 유지되었다. P. aeruginosa EMS1 및 mutant strain A34 모두 4% 농도에서 가장 높게 나타났다. 표면장력과 biosurfactant의 상대적인 양을 나타내는 Fcmc의 경우 P. aeruginosa EMS1 보다 mutant strain A34가 우수하게 나타났다. PCR 결과 P. aeruginosa EMS1은 rhlamnolipid의 coding 유전자인 rhlRAB gene을 가지는 것으로 확인되었다.

• Journal of Microbiology
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• v.43 no.5
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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.

• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.127-133
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• 2001

Pseudomonas aeruginosa KLP-2 possessing antimicro- bial activity against Legionella pneumophila was isolated from cooling tower-waters. The culture filtrates of P. aeruginosa KLP-2 showed antimicrobial activity against L. pneumophila Vibro cholerae non-Ol. Bacillus cereus, Bacillus subtilis and staphylococcus aureus. The culture filtrates of P. aeruginosa KLP-2 showed the highest anti-microbial activity against. L pneumophila among micoorganisms tested in this study. The optimal conditions of temperature, pH carbon source and nitogen source to obtain maximal antimicrobial activity from culture filtrates of P. aeruginosa KLP-2 were determined to be 35$^{\circ}C$ pH 7.0 % of glycerol and 0.6% of proteose peptone respec- tively. The antimicrobial activity of culture filtrates from P. seruginosa KLP-2 was highest against L. pneumophila when cultivated with shaking for 24 h and without shaking for 4 day at 35$^{\circ}C$.

• KSBB Journal
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• v.7 no.2
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• pp.118-125
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• 1992

Most of cosmetics are emulsion-type products which contain the sources of nutrition, i.e., vegetable oil, mineral oil and carbohyrate etc.. These additives are usually very susceptible to the contamination by microorganisms. The purpose of this study is to obtain the data necessary not only to prevent dermalopathia occurred by microbials but also to maintain the quality. In this experiment we observed the growth of P.aeruginosa in the cosmetics with or without antiseptics so as to prevent contamination. During the contamination period, the phase became unstable and creaming phenomina was happened together with some discoloration and bad smell. The pH of cosmetic was decreased from 7.6 to 6.0 and the concentration was increased from 1.443 to 1.453 in terms of refractive index during 40 days incubation. By adding antiseptics to the cosmetics, the number of P. aeruginosa from the challenge test method were decreased from $10^8$ cell/ml to $5{\times}10^3$ cell/ml. For the antibacterial effect against P. aeruginosa, p-hydroxy benzoic acid propyl ester in phosphoric acid buffer solution showed the best result.

• 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.

• Korean Journal of Microbiology
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• v.29 no.6
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• pp.345-352
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• 1991

A serine proteinase of molecular weight 60 kd was purified from culture supernatant of P. aeruginosa using DEAE-Trisacryl M ion-exchange and AcA 54 gel filtration column chromatography, and the properties of serine proteinase were characterized. By means of SDS-polyacrylamide gel electrophoresis, the molecular weight of the enzyme was 55 kd. The optimal pH for the activity of purified enzyme was 7.5. The activity of the purified enzyme was completely inhibited by Di-isopropylfluorophosphate(DFP) and N-.alpha.-p-tosyl-L-lysine choloromethyl detone(TLCK) but not by other proteinase inhibitors such as E-64, pepstatin A, 1, 10-phenanthroline. The purified enzyme was capable of degrading type I and type IV collagen. Antisera obtained from hymans infected with Pseudomonas aeruginosa reacted to the purified serine proteinase in immunoblots. These results indicate that the purified enzyme is trypsin-like serine proteinase and this enzyme of P. aeruginosa may play an important role in tissue damage as a spreading factor and may be useful for serodiagnosis of Pseudomonas infections.