• Korean Journal of Environmental Biology
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• v.18 no.3
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• pp.307-313
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• 2000

Aromatic hydrocarbons are known to be recalcitrant, so that they have been concerned as pollutant chemicals. Microorganisms play a major role in the breakdown and mineralization of these compounds. However, the kinetics of the biodegradation process may be much slower than desired from environmental consideration. The biodegradation of aromatic hydrocarbons is conducted by oxidation to produce catechol as a common intermediate which is metabolized for carbon and energy sources. In this study, a bacterial isolate capable of degrading several aromatic hydrocarbons was isolated from the contaminated wastewater of Yeocheon industrial complex. On the basis of biochemical characteristics and major cellular fatty acids, the isolate was identified as Pseudomonas putida Z104. The strain Z104 can utilize benzoate and catechol as the sole carbon and energy sources via a serial degradative pathway. The strain degraded actively 0.5 mM catechol in MM2 medium at pH 7.0 and 3$0^{\circ}C$.

• Research in Plant Disease
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• v.14 no.1
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• pp.32-36
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• 2008

Bacterial wilt caused by Ralstonia solanacearum has become a severe problem on tomato in Korea and no effective control measures are available yet. Pseudomonas species play key roles for the biocontrol of many plant diseases especially in soil. A rhizobacterial population of 150 Pseudomonas strains, isolated from the rhizosphere soil of various plants grown at different sites, was screened for 2,4-diacetylphloroglucinol producing gene (PhlD) by PCR. Two strains (P83 and P84) among them were found to be phlD positive. When the isolates were analysed by 16S rDNA (Sensu Stricto), all isolates yielded amplified products of 1,018bp. Of the 150 isolates of Pseudomonas spp., a bacterial strain P. putida P84 isolated from tomato rhizosphere showed to suppress a wide range of phytopathogenic bacteria in vitro. The best source of carbon for P84 strain were glucose, arabinose, inositol and melibiose. In greenhouse experiments, P84 strain suppressed the development of bacterial wilt in tomato with a control value of 60%.

• Korean Journal of Microbiology
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• v.29 no.3
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• pp.195-198
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• 1991

Isolation and identification of mesophilic and psychrotrophic bacteria distributed in Korean refrigerated beef were attempted. Total isolated colonies were 192, and identified as 5 genera and 10 species. Among them, mesophilic bacteria were Enterobacter aerogenes, E. agglomerans, Serratia liquefaciens, Proteus mirabilis, and "psychrotrophic" bacteria were Pseudomons fluorescens, P. putida, P. pickettii, P. mendocina, P. stutzeri, Alcaligenes faecalis. Dominant species was Serratia liquefaciens as mesophiles, and Pseudomonas putida as psychrotroph.chrotroph.

• Journal of Microbiology and Biotechnology
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• v.24 no.6
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• pp.835-842
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• 2014

Haloperoxidase (HPO, E.C.1.11.1.7) is a metal-containing enzyme oxidizing halonium species, which can be used in the synthesis of halogenated organic compounds, for instance in the production of antimicrobial agents, cosmetics, etc., in the presence of halides and $H_2O_2$. To isolate and evaluate a novel non-metal HPO using a culture-independent method, a cassette PCR library was constructed from marine seawater in Japan. We first isolated a novel HPO gene from Pseudomonas putida ATCC11172 by PCR for constructing the chimeric HPO library (HPO11172). HPO11172 showed each single open-reading frame of 828 base pairs coding for 276 amino acids, respectively, and showed 87% similarity with P. putida IF-3 sequences. Approximately 600 transformants screened for chimeric genes between P. putida ATCC11173 and HPO central fragments were able to identify 113 active clones. Among them, we finally isolated 20 novel HPO genes. Sequence analyses of the obtained 20 clones showed higher homology genes with P. putida or Sinorhizobium or Streptomyces strains. Although the HPO A9 clone showed the lowest homology with HPO11172, clones in group B, including CS19, showed a relatively higher homology of 80%, with 70% identy. E. coli cells expressing these HPO chimeric genes were able to successfully bioconvert chlorodimedone with KBr or KCl as substrate.

• Journal of Microbiology
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• v.41 no.2
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• pp.102-108
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• 2003

A 6.1 kb Sph I fragment from the genomic DNA of Pseudomonas putida SM 25 was cloned into the veetor pUC19. The open reading frame of catB was found to consist of 1,122 nucleotides. The sequence alignment of the catB gene products from different kinds of bacteria revealed an overall identity ranging from 40 to 98%. The catC gene contained an open reading frame of 96 codons, from which a protein with a molecular mass of about 10.6 kDa was predicted. The amino acids in the proposed activesite region of CatC were found to be almost conserved, including the charged residues. Since the catBC genes in P. putida SM25 were tightly linked, the could be regulated under coordinate transcription, and transcribed from a single promoter located upstream of the catB gene, as in P. putida RBI.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.11-14
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• 1998

A toluene-oxidizing strain of Pseudomanas mendocina KR1 containing toluene-4-mono-oxygenase (TMO) completely degrades TCE with the addition of toluene as a co-substrate in aerobic condition. In order to construct in situ bioremediation system for TCE degradation without any growth-stimulating nutrients or toxic inducer such as toluene, we used the carbon-starvation promoter of Pseudomonas putida MK1 (Kim, Y. et al., J. bacteriol., 1995). Upon entry into the stationary phase due to the deprivation of nutrients, this promoter is strongly induced without further cell growth. The TMO gene cluster (4.5 kb) was spliced downstream of the carbon starvation promoter of Pseudomonas putida MK1, already cloned in pUC19. TMO under the carbon starvation promoter was not expressed in E. coli cells either in stationary phase or exponential phase. For TMO expression in Pseudomonas strains, tmo and carbon starvation promoter region were recloned into a modified broad-host range vector pMMB67HES which was made from pMMB67HE(8.9 kb) by deletion of tac promoter and lacIq (about 1.5 kb). Indigo was produced by TMO under the carbon starvation promoter in a Pseudomonas strain of post-exponential phase on M9 (0.2% glucose and 1mM indole) or LB. 18% of TCE was degraded in 14 hours after entering the stationary phase at the initial concentration of 6.6 ${\mu}$M in liquid phase.

• 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.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.311-316
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• 2008

In this study, biological PCE degradation by using a BTEX degrading bacterium, named BJ10, under aerobic conditions in the presence of toluene was examined. According to morphological, physiological characteristics, 16S rDNA sequencing and fatty acid analysis, BJ10 was classified as Pseudomonas putida. As a result of biological PCE degradation at low PCE concentrations (5 mg/L), PCE removal efficiency by P. putida BJ10 was 52.8% for 10 days, and PCE removal rate was 5.9 nmol/hr (toluene concentration 50 mg/L, initial cell density 1.0 g (wet weight)/L, temperature 30, pH 7 and DO $3.0{\sim}4.2\;mg/L$. At high PCE concentration (100 mg/L), PCE removal efficiency by P. putida BJ10 was 20.3% for 10 days, and PCE removal rate was 46.0 nmol/hr under the same conditions. The effects of various toluene concentration (5, 25, 50, 100, 200 mg/L) on PCE degradation were examined under the same incubation conditions. The highest PCE removal efficiency of PCE was 57.0% in the initial PCE concentration of 10 mg/L in the presence of 200 mg/L toluene for 10 days. Furthermore, the additional injection of 5.5 mg/L PCE (total 7.6 mg/L) made 63.0% degradation for 8 days in the presence of 50 mg/L toluene under the same conditions. Its removal rate was 13.5 nmol/hr, which was better than the initial removal rate (8.1 nmol/hr).

• 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.

• Journal of Life Science
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• v.11 no.3
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• pp.235-241
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• 2001

To select the sntagonistic bacteria against B. cinerea, isolates were screened from the eggplant leaves and rhizosphere soils in the eggplnat fields in the greenhouse. W1 and P99 isolates were selected by the inhibition of mycelial growth of B. cinerea E12 in vitro test. These isolates, W1 and P99, were identified as Bacillus subtilis and Pseudomonas putida, respectively, by the Bergeys manual and API systems, For the formulation of the antagonistic bacteria, the media for the mass production were prepared with biji(soybean curd residues) or soybean flour. B. subtilis W1 or P. putida P99 was mass cultured in biji broth or soybean flour extrect broth and then soybean flour, corn starch flour, rice glutinous flour and biji flour as high molecular substrates were added. These mixtures were dried, grinded and formulated as brofungicides of wettable powder type. The assess the control effect of biofungicides against the infection of B. cinerea, six types of formulations were assayed at the pot culturing with eggplant in the greenhouse. According to the results, there were no significant differences among the formulation methods. However, P99S or PppB formulated with P. putida P99 showed the highest control values as 90.4% and 96.1%, respectively. Then. BSB or BSD formulated whit B. subtilis W1 were 80.8% and 83.0%, respectively. There afforementioned values were more effective than that of chemical fungicide. Ipro W.P which showed as 72.6%.