• Korean Journal of Environmental Agriculture
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• v.23 no.4
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• pp.197-202
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• 2004

The persistence of pendimethalin in soil and ground water has an injurious effect on ecosystem. Pendimethalin-degrading bacterium was isolated from Masan, Gyeongnam province and temporarily identified as Bacillus sp. MS202 by the analysis of API CHB50, kit, FAME, and 16S rDNA sequence. from the analysis of pnedimethalin metabolite using TLC, GC, and GC-MS, we found that the degradation of pendimethalin by Bacillus sp. MS202 did not result in the dealkylated form, but the formation of the reduced compound, 6-amino-2-nitro-N(1-ethylpropyl)-3,4-xylidine or 2- amino-6-nitro-N(1-ethylpropyl)-3,4-xylidine.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.346-356
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• 2011

BACKGROUND: Chemical fungicides not only may pollute the ecosystem but also can be environmentally hazardous, as the chemicals accumulate in soil. Biological control is a frequently-used environment-friendly alternative to chemical pesticides in phytopathogen management. However, the use of microbial products as fungicides has limitations. This study isolated and characterized a three-antifungal-enzyme (chitinase, cellulase, and ${\beta}$-1,3-glucanase)-producing bacterium, and examined the conditions required to optimize the production of the antifungal enzymes. METHOD AND RESULTS: The antifungal enzymes chitinase, cellulase, and ${\beta}$-1,3-glucanase were produced by bacteria isolated from an sawmill in Korea. Based on the 16S ribosomal DNA sequence analysis, the bacterial strain AM50 was identical to Streptomyces sp. And their antifungal activity was optimized when Streptomyces sp. AM50 was grown aerobically in a medium composed of 0.4% chitin, 0.4% starch, 0.2% ammonium sulfate, 0.11% $Na_2HPO_4$, 0.07% $KH_2PO_4$, 0.0001% $MgSO_4$, and 0.0001% $MnSO_4$ at $30^{\circ}C$. A culture broth of Streptomyces sp. AM50 showed antifungal activity towards the hyphae of plant pathogenic fungi, including hyphae swelling and lysis in P. capsici, factors that may contribute to its suppression of plant pathogenic fungi. CONCLUSION(S): This study demonstrated the multiantifungal enzyme production by Streptomyces sp. AM50 for the biological control of major plant pathogens. Further studies will investigate the synergistic effect, to the growth regulations by biogenic amines and antifungal enzyme gene promoter.

• Journal of Species Research
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• v.7 no.3
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• pp.231-239
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• 2018

While screening indigenous prokaryotic species in Republic of Korea in 2017, a total of 17 bacterial strains assigned to the phylum Bacteroidetes were isolated from a variety of environmental habitats including water of fountain, tidal flat, plant root, soil, the gut of Russian grayling butterfly, ginseng field, seawater, lagoon and seashore sand. From the 16S rRNA gene sequence similarity of more than 98.7% and the formation of a robust phylogenetic clade with the closest species, it was found that the 17 strains belong to independent and recognized bacterial species. There has been no official report that the identified 17 species have been previously isolated in the Republic of Korea. Thus, 15 species in 10 genera of one family in the order Flavobacteriales, one species in one genus of one family in the order Cytophagales, and one species in one genus of one family in the order Sphingobacteriales are proposed as unrecorded species of the phylum Bacteroidetes found in the Republic of Korea. Gram reaction, colony and cell morphology, basic phenotypic characteristics, isolation source, taxonomic status, strain ID and other information are described in the species descriptions.

• Journal of Species Research
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• v.7 no.3
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• pp.202-209
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• 2018

Eight bacterial strains, 18JY8-13, 18JY13-16, 18JY43-7, 18JY12-7, 18JY1-1, 18JY1-7, 18JY15-3, and 18JY7-2 assigned to the phylum Firmicutes were isolated from a variety of soil samples collected in the Jeju Island, Korea. Cells of the eight strains were Gram-positive, aerobic and showed resistant to UV-radiation. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strains 18JY8-13, 18JY13-16, 18JY43-7, 18JY12-7, 18JY1-1, 18JY1-7, 18JY15-3, and 18JY7-2 were most closely related to Bacillus paranthracis(99.9%), Bacillus paramycoides(99.6%), Bacillus australimaris(99.9%), Bacillus wiedmannii (100%), Bacillus halosaccharovorans(99.6%), Bacillus deserti(98.7%), Bacillus cereus (99.8%), and Bacillus albus(100%), respectively. This is the first report of these eight species in Korea.

• Journal of Species Research
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• v.9 no.2
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• pp.85-104
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• 2020

In 2019, after a comprehensive investigation of indigenous prokaryotic species in Korea, a total of 12 bacterial strains assigned to the phylum Proteobacteria were isolated from soil. With the high 16S rRNA gene sequence similarity (>98.8%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to independent, predefined bacterial species. This study identified two species in the family Burkholderiaceae, one species in the family Comamonadaceae, two species in the family Oxalobacteraceae, one species in the family Micrococcaceae, one species in the family Bradyrhizobiaceae, one species in the family Methylobacteriaceae, one species in the family Rhizobiaceae, one species in the family Rhodocyclaceae, and one species in the family Sphingomonadaceae. There is no official report about these 12 species in Korea, so are described as unreported bacterial species in Korea in this study. Gram reaction, basic biochemical characteristics, colony, and cell morphology are also described in the species description section.

• Research in Plant Disease
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• v.18 no.1
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• pp.54-56
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• 2012

Sclerotium rot of sponge gourd occurred at the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services in August 2010. The infected fruits showed water-soaked and rot symptoms. White mycelial mats spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, 1-3 mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$ and the hyphal width was 4-8 ${\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics, ITS rDNA sequence analysis, and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot on sponge gourd caused by S. rolfsii in Korea.

• Journal of Microbiology
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• v.43 no.4
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• pp.325-330
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• 2005

Rhodococcus sp. strain YU6 was isolated from soil for the ability to grow on o-xylene as the sole carbon and energy source. Unlike most other o-xylene-degrading bacteria, YU6 is able to grow on p-xylene. Numerous growth substrate range experiments, in addition to the ring-cleavage enzyme assay data, suggest that YU6 initially metabolizes 0- and p-xylene by direct aromatic ring oxidation. This leads to the formation of dimethylcatechols, which was further degraded largely through meta-cleavage path-way. The gene encoding meta-cleavage dioxygenase enzyme was PCR cloned from genomic YU6 DNA using previously known gene sequence data from the o-xylene-degrading Rhodococcus sp. strain DK17. Subsequent sequencing of the 918-bp PCR product revealed a $98\%$ identity to the gene, encoding meth-ylcatechol 2,3-dioxygenase from DK17. PFGE analysis followed by Southern hybridization with the catechol 2,3-dioxygenase gene demonstrated that the gene is located on an approximately 560-kb megaplasmid, designated pJY J1

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.329-331
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• 2017

Bacillus velezensis YC7010 is an endophytic bacterium isolated from the rice rhizosphere in Jinju, Republic of Korea, with properties conductive to growth promotion, antibiosis and induced systemic resistance to significant, soil-borne rice fungal and bacterial pathogens. The genome of B. velezensis YC7010 comprises a 3,975,683 bp circular chromosome which consists of 3,790 protein-coding genes (86tRNA and 27rRNA genes). Based on genomic analysis, we identified genes involved in colonization and establishment inside the plant, biosynthesis of antibiotic compounds such as surfactin, plipapastatin, bacillibactin, and bacillaene, as well as the production of the phytohormones and volatile compounds which serve to promote the plants growth and development.

• Journal of Species Research
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• v.8 no.4
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• pp.319-336
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• 2019

During an investigation of unrecorded prokaryotic species in Republic of Korea, a total of 53 bacterial strains belonging to the class Gammaproteobacteria were isolated from soil, seawater, tidal flats, rhizosphere, salt ponds, beach sand, urine, manure, sediment, and animal intestine (Russian grayling butterfly [Hipparchia autonoe], mouse [Mus musculus], and sea bass [Lateolabrax japonicus]). Strains were identified to species using the 16S rRNA gene sequence, showing high similarity (>98.7%) with the closest bacterial species and forming a robust clade in the neighbor-joining phylogenetic tree. The 53 strains of Gammaproteobacteria in this study have not been report previously in Korea. Therefore, we describe 27 genera of 16 families in 7 orders: 13 strains in the order Alteromonadales, 1 strain in the order Chromatiales, 11 strains in the order Enterobacterales, 7 strains in the order Oceanospirillales, 10 strains in the order Pseudomonadales, 8 strains in the order Vibrionales, and 3 strains in the order Xanthomonadales. Gram reaction, strain ID, isolation source, and morphological and basic biochemical characteristics are described for each species.

• Food Engineering Progress
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• v.14 no.3
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• pp.263-270
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• 2010

An alkalophilic microorganism named DK-2386, which produces xylanase, was isolated from soil of Taejo-mountain, Cheonan-si, Chungnam, Korea. The isolated strain was characterized as Gram-positive, with size of 0.4${\times}$2.5 ${\mu}$m, spore forming, anaerobic, catalase positive, possessed with hydrolysis abilities of casein, starch, sodium carboxy methyl cellulose, and xylan, reduction of nitrate to nitrite, resistant against lysozyme, urease positive, and motility positive. The color of culture broth was reddish yellow. The strain DK-2386 was identified as Bacillus agaradhaerens by whole cell fatty-acid composition analysis and 16S rDNA sequence analysis. However, it was not identical to Bacillus agaradhaerens 40952 obtained from the Korean Culture Center of Microorganism in its colour of culture broth. Therefore, we have named the newly isolated strain as Bacillus agaradhaerens DK-2386.