• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.236-240
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• 1989

The isolated bacterial strain 1K1 able to grow on extremely high concentration of toluene was morphologically and physiologically best described as Pseudomonas putida. This strain could grow on at least eight aromatic compounds, e.g., benzene, benzoate, phenol, o-cresol, m-cresol, toluene, m-tolunte, and xylene, but did not Brow on alkanes, such as hexane, octane, decane, and cyclohexane. Strain 1K1 could grow on above 95% toluene, but it could not grow on above 1% of other aromatic compounds. In the point of survival, strain 1K1 was resistant to high concentration of alkanes, appreciably resistant to toluene and xylene, and damaged by to other aromatic compounds. Strain 1K1 which grew on high concentration of toluene had irregular cell shape in comparing with normal cell shape of the genus Pseudomonas. Strain 1K1 was shown to have at least two aromatic compound dissimilation pathway, one for benzoate and the other for toluene.

• Korean Journal of Microbiology
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• v.25 no.1
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• pp.9-16
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• 1987

Three strains of bacteria utilizing salicylate, KU801(pKU5, pKU8), KU803(pKU6, pKU9), and KU806(pKU7, pKU10), were selected from the isolates and identified as Pseudomonas putida. By agarose gel electrophoresis, it was found that the strains had two plasmids each. All three strains were resistant to antibiotics such as ampicillin, tetracyclin, and chloramphenicol, and did not utilize other aromatic and aliphatic hydrocarbons examined except salicylate. The plasmids (pKU5, pKU6, and pKU7) of larger molecular weight were cured by treatment with mitomycin C and frequencies of curing were 0.4%, 1.67%, and 0.75%, respectively. Cured strains did not degrade salicylate and still had antibiotic resistances, which were identical with wild strains. The genes for salicylate degradation were proved to be enclded on thier plasmids. The molecular weights of pKU5 and pKU6 were estimated as 103.5Md, and that of pKU 7 as 101 Md. The new SAL plasmids, pKU5, pKU6, and pKU7 were transferred to P. putida and P. aeruginosa, but not to E. coli.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.106-112
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• 1986

The large plasmid (about 180 megadaltons) was isolated from the aquatic strain of Pseudomonas which was found to degrade salicylate. It was found that the plasmid could be isolated under gentle conditions in comparison with other methods. The yield of covalently closed circular DNA was enganced by heat treatment at $55^{\circ}C$ after denaturing the chromosomal DNA with alkaline sodium dodecyl sulfate (pH 12.45), and the plasmid DNA was selectively concentrated by utilizing 10% polyethylene glycol as final concentration. It was also found that the cured strains with mitomycin C did not show any growth on the medium containing salicylat6e, therefore, it was concluded that the plasmid might play and important role on the salicylate degradation.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.240-245
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• 1991

We have constructed a promoter-probe vector pKU20 using pKT230, a derivative of broad-host-range plsmid RSF1010, as a base. The pKU20 contains structural gene for aminoglycoside phos-photransferase (aph), without promoter, and a multiple cloning site upstream the aph. Using this vector, a 412base pairs (bp) PstI fragment showing strong promoter activity both in Escherichia coli LE392 and Pseudomonas putida KCTC1644 has been cloned from Pseudomonas fluorescens chromosomal DNA on the basis of streptomycin resistance. The nucleotide sequence of the 412 bp fragment has been determined and the putative - 35 and -10 region was observed. Insecticidal protein gene of Bacillus thuringiensis subsp. kurstaki HD-73 inserted on downstream of the promoterlike DNA fragment was efficiently expressed in E. coli and P. putida. The toxin protein was efficiently synthesized in an insoluble form in both strains.

• Korean Journal of Microbiology
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• v.30 no.5
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• pp.410-414
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• 1992

Numerical identification was carried out for an isolate of Streptomyces strain producing the extracellular p-lactamase inhibitor. Fifty taxonomic unit characters were tested and the data were analyzed numerically using the TAXON program. The isolate was identified to the major cluster 5 of Streptomyces and it was best matched to Streptomyces omiyaensis which is a synonym of Streptomyces exfoliatus. Therefore, it was concluded that the isolate was identified to be a strain (SMF 19) of Streptomyces exjbliatus.

• Korean Journal of Microbiology
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• v.30 no.3
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• pp.207-212
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• 1992

To develope the new strains of microorganisms having the degradative ability for various aromatic hydrocarbons. spheroplast cell fusions were performed with Arthrobacter spp. degrading phthalate ester and Pseudomonas putida degrading alkylbenzen sulfonate(ABS) and the characteristics of the fusants were investigated. The spheroplasts of P. putia KUD15 and Arthrobacter sp. were formed effectively by lysozyme-EDTA treatment and by Ampicillin-lysozyme-EDTA treatment. respectively. The Spheroplast formation frequency and the regeneration frequency of the strains were 98-99% and 5-8%, respectively. For cell fusion. 40% PEG6000 was used as a fusogenic agent and the formation frequencies of fusion product were $1.8{\times}10^{4}-$2.9{\times}10^{4}$ Most of the fusants, which were selected in complemented antibiotics media showed the degradative ability in minimal selective medium added phthalate ester or ABS as sole carbon source. ABS degradation by fusant strain was increased about 20% with compared with the parental strain, while the degradative ability of phthalate ester was simillilar to that of parental strain.

• Research in Plant Disease
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• v.12 no.3
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• pp.267-271
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• 2006

Botrytis cinerea Pers. was found to be highly virulent to the grapevine plant, especially in greenhouse condition. Pseudomonas species play key roles for the biocontrol of many plant diseases especially in soil. Of the 83 isolates of Pseudomonas spp., a bacterial strain P84, isolated from tomato rhizosphere, was shown to suppress a wide range of phytopathogenic fungi in vitro. The isolate was identified as Pseudomonas putida on the basis of its bacteriological and genetic characteristics. The P. putida P84 strain carry the phlD gene for 2,4-diacetylphloroglucinol biosynthesis and may produce the antibiotics as an antagonistic mechanism involved in biocontrol. The antagonistic activity of the bacterium has a promising implication for its use as a biocontrol agent to control grapevine gray mold.

• Korean journal of applied entomology
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• v.22 no.3 s.56
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• pp.186-192
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• 1983

The growth of germ tube of Fusarium oxysporum f. sp. cucumerinum was remarkably inhibited on the water agar treated with 100ppm of Fe-EDDHA, a synthetic iron chelating agent, whereas germination rate of microconidia did not show much differences compare with that of non treated water agar. Both of the germination and the germ tube elongation of microconidia were suppressed significantly in King's B agar by the bacterial siderophores produced by Pseudomonas putida. The highest germination of the chlamydospores was obtained in the soil added with $0.25\%$ of glucose plus $0.05\%$ of asparagine. The chlamydospores of cucumber wil fungus germinated about $14\%$ in rhizosphere soil of 2 day-old cucumber seedlings within 48 hours, and the germination was enhanced notably in rhizosphere soil of 10 day-old seedling. But the rates of germination was not increased according to cucumber growth age after 10 day-old seedling. The effect of P. putida and Fe-EDDHA on the germination on chlamydospores in conducive soil was not pronounced in the non-rhizosphere soil added with nutrient. However, the germination was suppressed significantly both in rhizosphere soil and in rhizosphere soil added with nutrient. The suppression of chlamydospore germination was greater in the bacteria inoculated soil than that in Fe-EDDHA treated soil.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1330-1335
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• 2011

N-Acyl homoserine lactones (AHLs) serve as the vital quorum-sensing signals that regulate the virulence of the pathogenic bacterium Erwinia carotovora. In the present study, an approach to efficiently restrain the pathogenicity of E. carotovora-induced soft rot disease is described. Bacillus thuringiensis-derived N-acyl homoserine lactonase (AiiA) was projected onto the surface of Pseudomonas putida cells, and inoculation with both strains was challenged. The previously identified N-terminal moiety of the ice nucleation protein, InaQ-N, was applied as the anchoring motif. A surface display cassette with inaQ-N/aiiA was constructed and expressed under the control of a constitutive promoter in P. putida AB92019. Surface localization of the fusion protein was confirmed by Western blot analysis, flow cytometry, and immunofluorescence microscopy. The antagonistic activity of P. putida MB116 expressing InaQ-N/AiiA toward E. carotovora ATCC25270 was evaluated by challenge inoculation in potato slices at different ratios. The results revealed a remarkable suppressing effect on E. carotovora infection. The active component was further analyzed using different cell fractions, and the cell surface-projected fusion protein was found to correspond to the suppressing effect.

• Journal of the Korean Chemical Society
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• v.13 no.4
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• pp.355-364
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• 1969

Cross-hybridizations between DNA of two pseudomonads and a xanthomonad suggested that the three DNA types had a considerable section in common. The existence of this common part was proved by hybridization of preselected DNA, i.e. DNA resulting from a previous hybridization between any one set of two DNA types, with the third type. It was thus shown that about 50% of the DNA of the three organisms was similar. This common part was isolated in pure state and its % (G+C) was found to be indentical to the overall base composition of the native DNA. The evolutionary drift in % (G+C) could thus not be detected. The total molecular weight of the chromosornal DNA/bacterial nucleoid was determined to be 2.4 ${\times} 10^9$daltons. It can therefore be estimated that the common putida-fluorescenspelargonii DNA part consists of some 2,000 cistrons. P. putida and P. fluorescens share an additional 1,300 cistrons, and all xanthomonads share at least an additional 1,000 cistrons.