• Korean Journal of Microbiology
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• v.28 no.3
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• pp.236-242
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• 1990

To develop the new strains of microorganisms having the degradative ability for various aromatic hydrocarbons, the hybrid plasmid pKG2 having the 2,4-Dichlorophenoxyacetic acid(2,4-D) degradative genes, the hybrid plasmid pKG3 containg the naphthalene degradative genes and TOL plasmid were introduced into Pseudomonas putida KUD 12 and P. putida KUP 10 by transformation or conjugation which originally have the degradative ability of the synthetic surfactants and phthalate esters, respectively. From P. putida KUD12, the new strains of P. putida KUD101(pKG2), KUD102(pKG3), KUD103(TOL), and KUD202(pKG3, TOL) were obtained, and KUD106(pKG2), KUD107(pKG3), KUD108(TOL) were originated from the P.putida KUP10. The degradative abilities in P. putida KUD101, KUD102 and KUD107 were similar with those of the original strains. The P. putida KUD103, KUD106 and KUD202 had a little lower and P. putida KUD108 had a better degradative abilitie than those of the original ones. In the case of mixed cultures, the mixed culture of KUD107 and KUD108 had a better degradative abilities than those of the other mixed cultures.

• Korean Journal of Microbiology
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• v.24 no.4
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• pp.389-393
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• 1986

From the soil and river samples, some bacterial strains degrading chlorinated aromatic hydrocarbons were isolated and identified. Of the isolates, seven strains of Pseudomonas sp. harbouring plasmids were selected for their prominent degradative ability to 2-methyl-4-chlorophenoxyacetic acid. By agarose gel electrophoresis and curing experiment it was found that the genes for 2-methyl-4-chlorophenoxyacetic acid degradaiton were encoded on the plasmids in these selected strains. Antobiotic resistance and degradative ability for other herbicides of the strains were tested.

• 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.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.83-85
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• 2019

Pseudomonas sp. PAMC 29040 was isolated from a maritime tundra soil in Antarctica for its ability to degrade lignin and subsequently confirmed to be able to depolymerize heterogeneous humic substance (HS), a main component of soil organic matter. The draft genome sequences of PAMC 29040 were analyzed to discover the putative genes for depolymerization of polymeric HS (e.g., dye-decolorizing peroxidase) and catabolic degradation of HS-derived small aromatics (e.g., vanillate O-demethylase). The information on degradative genes will be used to finally propose the HS degradation pathway(s) of soil bacteria inhabiting cold environments.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.177-179
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• 2019

Pseudomonas kribbensis CHA-19 was isolated from a temperate forest soil (mid latitude) in New Jersey, USA, for its ability to degrade humic acids, a main component of humic substances (HS), and subsequently confirmed to be able to decolorize lignin (a surrogate for HS) and catabolize lignin-derived ferulic and vanillic acids. The draft genome sequence of CHA-19 was analyzed to discover the putative genes for depolymerization of polymeric HS (e.g., dye-decolorizing peroxidases and laccase-like multicopper oxidases) and catabolic degradation of HS-derived small aromatics (e.g., vanillate O-demethylase and biphenyl 2,3-dioxygenase). The genes for degradative activity were used to propose a HS degradation pathway of soil bacteria.

• Journal of Life Science
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• v.21 no.5
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• pp.700-705
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• 2011

Using enrichment procedures, we isolated organic solvent-tolerant Bacillus sp. BCNU 5005 from waste water and soil in the Ulsan industrial plant region. BCNU 5005 had a maximum similarity of 98% with B. subtilis and was designated as B. subtilis based on phylogenetic analyses using 16S rDNA sequences. Generally, most bacteria and their enzymes are destroyed or inactivated in the presence of high concentrations of organic solvents. However, the lipase activity of B. subtilis BCNU 5005 was very stable in the presence of various kinds of solvents (25%, v/v) except chloroform, ethylbenzene and decane. Furthermore, BCNU 5005 was determined to have a degradative ability towards organic solvents. This organic solvent tolerant Bacillus sp. BCNU 5005 could be used as a new potential resource for biotransformation and bioremediation.

• Korean Journal of Microbiology
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• v.24 no.4
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• pp.394-399
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• 1986

From the lysates of the 7 selected strains of Pseulomonas utilizing 2-methyl-4-chlorophenoxyactate as a sole source of carbon and energy, several MCPA plasmids, which encodes genes for the degradation of 2-methyl-4-chlorophenoxyacetate, were isolated, and measured their molecular weight as well as genetic characters such as resistance to antibiotics and degradative ability of other chlorinated herbicides. Transmissibility of the MCPA plasmids, pKU1, pKU15, and pKU17 was tested by conjugation or transformation and the restriction pattern of pKU15 for Pvu II, Hind III, EcoR I, Xho I, Bgl II, and Ava II was analyzed.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1037-1051
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• 2018

The genus Rhodococcus is a phylogenetically and catabolically diverse group that has been isolated from diverse environments, including polar and alpine regions, for its versatile ability to degrade a wide variety of natural and synthetic organic compounds. Their metabolic capacity and diversity result from their diverse catabolic genes, which are believed to be obtained through frequent recombination events mediated by large catabolic plasmids. Many rhodococci have been used commercially for the biodegradation of environmental pollutants and for the biocatalytic production of high-value chemicals from low-value materials. Recent studies of their physiology, metabolism, and genome have broadened our knowledge regarding the diverse biotechnological applications that exploit their catabolic enzymes and pathways.

• Journal of Microbiology
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• v.42 no.2
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• pp.87-93
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• 2004

Twelve mecoprop-degrading bacteria were isolated from soil samples, and their genetic and phenotypic characteristics were investigated. Analysis of 16S rDNA sequences indicated that the isolates were related to members of the genus Sphingomonas. Ten different chromosomal DNA patterns were obtained by polymerase-chain-reaction (PCR) amplification of repetitive extragenic palindromic (REP) sequences from the 12 isolates. The isolates were found to be able to utilize the chiral herbicide meco-prop as a sole source of carbon and energy. While seven of the isolates were able to degrade both (R)-and (S)-mecoprop, four isolates exhibited enantioselective degradation of the (S)-type and one isolate could degrade only the (R)-enantiomer. All of the isolates were observed to possess plasmid DNAs. When certain plasmids were removed from isolates MPll, MP15, and MP23, those strains could no longer degrade mecoprop. This compelling result suggests that plasmid DNAs, in this case, conferred the ability to degrade the herbicide. The isolates MP13, MP15, and MP24 were identified as the same strain; however, they exhibited different plasmid profiles. This indicates that these isolates acquired dif-ferent mecoprop-degradative plasmids in different soils through natural gene transfer.

• Proceedings of the Microbiological Society of Korea Conference
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• 2001.11a
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• pp.157-163
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• 2001

Mycolic acid-containing gram-positive bacteria, so called nocardioform actinomycetes, have become a great interest to environmental microbiologists due to their metabolic versatility, multidegradative capacity and potential for bioremediation of priority pollutants. For example, Rhodococcus rhodochrous N75 was able to metabolize 4-methy1catechol via a modified $\beta$-ketoadipate pathway whereby 4-methylmuconolactone methyl isomerase catalyzes the conversion of 4-methylmuconolactone to 3-methylmuconolactone in order to circumvent the accumulation of the 'dead-end' metabolite, 4-methylmuconolactone. R. rhodochrous N75 has also shown the ability to transform a range of alkyl-substituted catechols to the corresponding muconolactones. A novel 3-methylmuconolactone-CoAsynthetase was found to be involved in the degradation of 3-methylmuconolactone, which is not mediated in a manner analogous to the classical $\beta$-ketoadipate pathway but activated by the addition of CoA prior to hydrolysis of lactone ring, suggesting that the degradative pathway for methylaromatic compounds by gram-positive bacteria diverges from that of proteobacteria. Mycobacterium sp. Strain PYR-l isolated from oil-contaminated soil was capable of mineralizing various polyaromatic hydrocarbons (PAHs), such as naphthalene, phenanthrene, pyrene, fluoranthrene, 1-nitropyrene, and 6-nitrochrysene. The pathways for degradation of PAHs by this organism have been elucidated through the isolation and characterization of chemical intermediates. 2-D gel electrophoresis of PAH-induced proteins enabled the cloning of the dioxygenase system containing a dehydrogenase, the dioxygenase small ($\beta$)-subunit, and the dioxygenase large ($\alpha$)-subunit. Phylogenetic analysis showed that the large a subunit did not cluster with most of the known sequences except for three newly described a subunits of dioxygenases from Rhodococcus spp. and Nocardioides spp. 2-D gel analysis also showed that catalase-peroxidase, which was induced with pyrene, plays a role in the PAH metabolism. The survival and performance of these bacteria raised the possibility that they can be excellent candidates for bioremediation purposes.