• 환경위생공학
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• 제13권3호
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• pp.113-120
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• 1998

For a microbial control of a plant pathogenic Pseudomonas syringae, Bacillus sp. strain BT182-3 was isolated. The strain BT182-3 had a growth inhibition against P. syringae not only on agar plate but also on cultured broth. After heat treatment at $40^{\cird}C$ and $80^{\cird}C$ for 30min, the lytic substance from the strain BT182-3 had about 52% remaining activity and 17% remaining activity, respectively. The optimal pH and temperature of the lytic substance was 6.0 and $28^{\cird}C$, respectively. Germination ratio of healthy radish seeds was 87% at $25^{\cird}C$ for 5 days in 0.8% saline, and that of the radish seeds infected with P. syringae was 67%, while that of the radish seeds treated with cultured broth of the strain BT182-3 was 90%. The 5-days healthy radish seedlings were 3.90cm at high and the seedlings infected with P. syringae were 3.06cm at high, while the seedlings treated with cultured broth of the strain BT182-3 were 4.30cm at high. The growth of the radish seedlings infected with P. syringae was inhibited after cultivation for 40days on pots, while the growth of the infected radish seedlings with P. syringae was recovered at stem length, root length and total weight at the same as the healthy seedlings after treatment of a lytic substance from the strain BT182-3.

• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.50-55
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• 2001

Different polluted water samples were collected from a wastewater treatment plant, agricultural drainage canals, the River Nile, and irrigation canals. The samples were examined for the enumeration of Pseudomonas aeruginosa in the Sohag area, Egypt over a period of one year. A total of 240 isolates were collected and tested for their resistance to 12 common antibiotics and 6 heavy metals. The isolates were found to be less resistant to norfloxacin(1.7%), ofloxacin(4.6%), amikacin(9.6%), tobramycin (10.4), carbenicillin (15.4), and gentamycin (41.3%), yet more sensitive to rifampicin (75%), kanamycin (89.6%), ampicillin (90.8%), chloramphenicol (91.7%), streptomycin (92.9%), and tetracyclin(96.3%). In contrast, 7.1%, 12.9%, 25.4%, and 53.7% of the isolates were resistant to lead, cadmium, mercury, and zinc, respectively. None of the isolates had developed a resistance to silver or molybdenum. The high frequency of metal-antibiotic double resistance existed between lead and amikacin (56.5%), cadmium and ofloxacin (72.7%), zinc and norfloxacin (100%), and mercury and carbenicillin (94.6%). The high occurrence of antibiotic-resistant bacteria in natural water could be related to the widespread use of antibiotics, with possible public health hazard.

• Journal of Microbiology
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• 제37권4호
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• pp.200-205
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• 1999

7-Aminocephalosporanic acid (7-ACA) is the initial compound in preparation of cephalosporin antibiotics widely used in clinical treatment. Bacteria producing glutaryl 7-ACA acylase, which convert cephalosporin C to 7-ACA, has been screened in soil samples. A bacterial strain exhibiting high glutaryl 7-ACA acylase activity, designated KAC-1, was isolated and identified as a strain of Pseudomonas diminuta by characterizing its morphological and physiological properties. The screening procedures include culturing on enrichment media containing glutaric acid, glutamate, and glutaryl 7-aminocephalosporanic acid as selective carbon sources. To enhance enzyme production, optimal cultivation conditions were investigated. This strain grew optimally at pH 7 to 9 and in temperatures of 20 to 40 C, but acylase production was higher when the strain was grown at 25 C. Glutaric acid, glutamate and glucos also acted as inducers for acylase production. In a jar fermenter culture, P. diminuta KAC-1 produce acylase in a growth-associated manner. The substrate specificity of KAC-1 acylase by cell extract showed that this enzyme had specificity toward glutaryl 7-ACA, glutaryl 7-ADCA, but not cephalosporin C.

• Journal of Microbiology and Biotechnology
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• 제18권4호
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• pp.773-777
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• 2008

Phosphate solubilizing bacteria (PSB) were isolated from the rhizosphere of Chinese cabbage and screened on the basis of their solubilization of inorganic tricalcium phosphate in liquid cultures. Ten strains that had higher solubilization potential were selected, and they also produced indole-3-acetic acid, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and siderophores. The strains were identified to be members of Pseudomonas, by 16S rDNA sequence analysis. Seed bacterization with PSB strains increased the root elongation and biomass of Chinese cabbage in seedling culture, although they had no effect on phosphorus uptake of plants. The plant growth promotion by PSB in this study could be due to the production of phytohormones or mechanisms other than phosphate solubilization, since they had no effect on P nutrition.

• 한국환경과학회지
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• 제15권12호
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• pp.1185-1191
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• 2006

The high surface area polymer, AquaMats$^{circledR}$ was used for the leachate purification process originated from the Samsan Dong Landfill in Ulsan Metropolitan City. And then, three species of dominant microbes were isolated and identified from AquaMats$^{circledR}$. Gram staining revealed these microbes to be Gram-negative rod strains: They were identified as Agrobacterium radiobacter, Pseudomonas cepacia, Flavobacterium indologenes. All they showed no growth on media in which the leachate was added alone, but a rapid proliferation rate on media with yeast extract as nutrient requirements.

• 미생물학회지
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• 제23권3호
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• pp.230-234
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• 1985

Malonate를 유일한 탄소원으로 활용할 수 있는 세균을 토양으로부터 분리하였다. 이 세균은 행태, 배양, 생리 그리고 생화학적 연구를 통하여 Acinetobacter calcoaceticus임이 확인되었다. 이 미생물을 malonate를 유일한 탄소원으로 하는 배지에서 배양하였을 갱우, malonyl CoA synthetase, isocitrate lyase 및 malate, synthase가 유도 되었다. 따라서 이 미생물에서도 Pseudomonas fluorescens에서 제안되었던 대사경로 즉 $malonate{\rightarrow}malonyl-CoA{\rightarrow}acetyl-CoA{\rightarrow}glyoxylate\;cycle$을 통하여 malonate를 이용하는 것으로 판단된다.

• Applied Biological Chemistry
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• 제31권1호
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• pp.33-37
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• 1988

김치에서 분리한 Pediococci를 동정한 결과 Pediococcus pentosaceus, Pediococcus acidilactici 및 Pediococcus halophilus의 세종으로 밝혀졌다. 이 Pediococci의 미생물 생육저해 작용을 조사한 결과 P. pentosaceus는 모두 Streptococcus faecalis와 Pseudomonas sp., P20에 대하여 생육저해작용을 나타내었다. P. acidilatici는 S. faecalis와 Vibrio parahaemolyticus의 생육을 저해하였으나 P. halophilus는 4종의 test organism에 대하여 저해작용이 없었다. 이들 Pedicocci는 균주에 따라 한개로 부터 일곱개의 plasmid DNA를 가지고 있으며 그 분자량은 약 1 Mdal에서부터 약 60 Mdal 사이의 여러 크기의 plasmid DNA가 존재함이 밝혀졌다.

• Journal of Microbiology and Biotechnology
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• 제4권4호
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• pp.338-342
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• 1994

The bacterium producing EPA was isolated from the intestines of the marine fishes. The strains were studied for their identification and their culture conditions. The selected strain was gram negative, rod(0.7 $\times$ 2.4 $\mu m$ in size) and motile with a single polar flagellum. This strain was identified as a Pseudomonas sp. on the basis of its morphological, cultural and physiological characteristics. The strain showed a maximum productivity of phospholipid at $20^{\circ}C$ after 48 hours of culture time with an initia1 pH of 7.0 in the PYM-glucose medium. Under these culture conditions, the production of phospholipid was about 0.3 mg/ml and 0.06 mg/mg dry cell weight.

• Ocean and Polar Research
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• 제27권2호
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• pp.215-219
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• 2005

We isolated and identified three protease-producing bacteria that had inhabited the region around the Korean Arctic Research Station Dasan located at Ny-Alesund, Svalbard, Norway $(79^{\circ}N,\;12^{\circ}E)$. Biofilms were collected from the surface of a floating pier and from dead brown algae in a tide pool near the seashore. The biofilm samples were transported to the Korea Polar Research Institute (KOPRI) under frozen conditions, diluted in sterilized seawater, and cultured on Zobell agar plates with 1% skim milk at $10^{\circ}C$. Three clear zone forming colonies were selected as protease-producing bacteria. Phylogenetic analysis based on 16S rDNA sequences showed that these three stains shared high sequence similarities with Pseudoalteromonas elyakovii, Exiguobacterium oxidotofewm Pseudomonas jessenii, respectively. We expect these Arctic bacteria may be used to develop new varieties of protease that are active at low temperatures.

• 한국미생물·생명공학회지
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• 제41권1호
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• pp.79-87
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• 2013

An unstable yet efficient phenanthrene-degrading bacterium strain Ph-3 was isolated from a petroleum-contaminated site at the Mathura Oil Refinery, India. The strain was identified as Pseudomonas sp. using a polyphasic approach. An analysis of the intermediates and assays of the degradative enzymes from a crude extract of phenanthrene-grown cells showed a novel and previously unreported pattern of 1, 2-dihydroxy naphthalene and salicylic acid production. While strain Ph-3 lost its phenanthrene- degrading potential during successive transfers on a rich medium, it maintained this trait in oligotrophic soil conditions under the stress of the pollutant and degraded phenanthrene efficiently in soil microcosms. Although the maintenance and in vitro study of unstable phenotypes are difficult and such strains are often missed during isolation, purification, and screening, these bacteria constitute a substantial fraction of the microbial community at contaminated sites and play an important role in pollutant degradation during biostimulation or monitored natural attenuation.