• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.162-168
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• 1996

우리 나라의 주요 고추 재배지와 미국, 대만, 호주, 아르헨티나에서 수집된 44 개 고추 더뎅이병균(Xanthomonas campestris pv. vesicatoria)균주간의 유전적변이를 genomic DNA의 restriction fragment length polymorphism(RFLP)에 의해 분석하였다. Genomic DNA RFLP profiles을 cluster 분석하여 얻은 dendrogram에서 지리적 기원이 다른 44개 균주들은 11개 RFLP 그룹으로 분류되었다. 외국 균주들은 genomic DNA의 RFLP 분석에 의해 모두 각각 다른 RFLP 그룹으로 분류되었다. 외국 균주들 중에서 미국 균주는 우리 나라 일부 균주들과 밀접한 유전적 관련성을 가지고 함께 cluster를 이루었는데, 이것은 이 균주들이 동일한 고추 더뎅이병균의 조상 균주 집단에서 유래했으리라는 것을 시사해 준다. 우리 나라 균주들은 6개의 RFLP 그룹으로 분류되었다. 대부분의 우리 나라 균주들은 가까운 cluster를 이루며 미국 균주를 제외한 외국 균주들과 뚜렷하게 구분되었다. 그러나 우리 나라 균주들 중에서 마산에서 수집된 Ms93-1은 다른 우리 나라 균주들과 뚜렷하게 구분되었다. 유전적으로 격리된 균주의 출현은 우리 나라에서 지리적 기원이 다른 고추 더뎅이병균 균주 사이에 이미 발생한 다양한 유전적 분화의 결과라고 추론된다.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.321-323
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• 2006

A combination of thymol and sodium bisulfate was found to be an effective biocidal agent against strains of Burkholderia cepacia and of Xanthomonas maltophilia that were found in the space shuttle water system. Potassium iodide (KI), the biocidal agent used in the past, had a minimum inhibitory concentration (MIC) of 50,000 ppm against the two B. cepacia (541 STS-81 and 1119 STS-91) strains, whereas that of thymol and sodium bisulfate was 2,400 and 950 ppm, which was 21 and 53 times lower than that of KI for B. cepacia, respectively. The MIC value for the combination of thymol and sodium bisulfate was 4 times lower than that for thymol or sodium bisulfate alone against B. cepacia (541 STS-81, 1119 STS-91) or Pseudomonas cepacia (ATCC 31941). The fractional inhibitory concentration (FIC) of the combination of thymol and sodium bisulfate for all organisms tested was less than 0.5, indicating a strong synergistic effect.

• The Plant Pathology Journal
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• v.19 no.4
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• pp.205-209
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• 2003

Dispersal of citrus bacterial canker caused by Xanthomonas axonopodis pv. citri on Unshiu orange was investigated in naturally infested nursery plot at Seogwipo in Jeju island, Korea. Based on phage detection, over 2% of the bacterial pathogen over-wintered in canker lesions and started to multiply in late May. However, symptoms were first observed 1 month after the phage detection. The disease dispersed non-directionally to nearby plants possibly because of indirect dissemination of the bacterium by rain splashes. The disease increased from late June to late August and decreased thereafter. Population of phage increased constantly, however, disease occurrence somewhat fluctuated due to environmental factors. Disease incidence and severity were correlated with rainfall with wind that occurred 14-32 days earlier from late May to late August.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.115-118
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• 1999

A new bacterial disease was found on trees of peach(Prunus persica var. vulgaris Max) at Kumho Kyungbuk in April 1999. The disease usually occured on over wintered buds branchs and stems of the Cheon-Hong cultivar. The buds died without sprouting and the branches showed entire wilting Droplets of bacterial ooze was occasionally running down the surface of diseased plants under moist condition. Artificial needle prick inoculation with isolates obtained from branchs of naturally infected plants produced symptoms similar to those occuring under natural condition. On the basis of bacteriological characteristics and pathogenicity on the host plant of the organism the causal bacterium was identified as Xanthomonas arboricora pv. pruni and this disease was proposed to name "Bacterial branch blight of the peach tree"

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.359-363
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• 2007

Because of the importance of the type III protein-secretion system in bacteria-plant interaction, its function in bacterial pathogenesis of plants has been intensively studied. To identity bacterial proteins interacting with Xanthomonas hrp gene products that are involved in pathogenicity, we performed the glutathione-bead binding analysis of Xanthomonas lysates containing GST-tagged Hrp proteins. Analysis of glutathione-bead bound proteins by 1-DE and MALDI-TOF has demonstrated that Avr proteins, RecA, and several components of the type III secretion system interact with HrpB protein. This proteomic approach could provide a powerful tool in finding interaction partners of Hrp proteins whose roles in host-pathogen interaction need further studies.

• Plant Resources
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• v.7 no.1
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• pp.65-68
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• 2004

We used an amplified fragment length polymorphism (AFLP) analysis, a novel PCR-based technique, to differentiate Xanthomonas oryzae pv. oryzae (Xoo) of Korean races. The 6 strains of Xoo K1, K2, K3 races were tested with 81 AFLP primer combinations to identify the best selective primers. The primer combinations were selected according to their reproducibility, number of polymorphic bands and polymorphism detected among Xoo strains. 18 strains of Xoo K1, K2 and K3 races were analyzed with the selected combinations of primer set. Some primer combinations (Eco R I +1 / Mse I+1) could differentiate Xoo of Korean races that were not distinguished by other fingerprinting analysis. Thus AFLP fingerprinting permitted very fine discrimination among different races.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2071-2078
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• 2018

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight, which results in severe economic damage to rice farms. Xoo produces biofilms for pathogenesis and survival both inside and outside the host. Biofilms, which are important virulence factors, play a key role in causing the symptoms of Xoo infection. In the present study, we investigated the nutritional conditions for biofilm formation by Xoo. Although Xoo biofilm formation may be initiated by interactions with the host, Xoo biofilm cannot mature without the support of favorable nutritional conditions. Nitrogen sources inhibited Xoo biofilm formation by overwhelming the positive effect that cell growth has on it. However, limited nutrients with low amino acid concentration supported biofilm formation by Xoo in the xylem sap rather than in the phloem sap of rice.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.179-183
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• 1997

We have screened hypersensitive responses of 18 cultivars of Nicotiana tabacum to Xanthomonas campestris pv. campestris. TC500 cultivar produced the most strong hypersensitive response (HR) to Xanthomonas campestris pv. campestris. By NTG mutagenesis, nonhypersensitive mutants (XHN 514-774, XHN 620-831) were generated, which does not induce hypersensitive response on tobacco leaves (Nicotiana tabacum cv. TC500). Also nonpathogenic mutant (XPN 1001), which does not incite any of the black rot symptoms on leaves was generated. We observed that HR mutants were still pathogenic on cabbage leaves producing black rot symptoms and nonpathogenic mutant induced HR in tobacco leaves. The inplanta growth of wild type and HR mutants were examined for up to 120 hrs after inoculation : population of wild type strain increased to $10^{8}$ in 24hrs, but rapidly declined thereafter; HR-mutants increased to more than $10^{6}$ in 48 hrs after inoculation but subsequently stabilized and slowly decreased. We observed that wild type and these mutans produced similar amounts of degradative enzymes such as protease, pectate lyase, cellulase and amylase.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.359-365
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• 2010

Fifty Actinobacteria strains were isolated from rhizosphere soil of Sasa borealis. In the course of screening for antibacterial activity against bacterial leaf spot of pepper (Xanthomonas axonopodis pv. vesicatoria) of isolates, 12 isolates showed strong antibiotic activity. Basis on the 16S rRNA gene sequence, they were belonging to Streptomyces cluster II. Strain JR-24 exhibited strong antibiotic activity against X. axonopodis pv. vesicatoria, had a minimum inhibitory concentration of 10 ${\mu}l$/disc. The strain JR-24 was most closely related to Streptomyces galbus $DSM40089^T$ (98.1%), Streptomyces longwoodensis $LMG20096^T$ (98%) and Streptomyces capoamus $JCM4734^T$ (97.8%). When assayed with the API 20NE and 50 CHE kit, it is positive for utilization of L-arabinose, D-fructose, D-glucose, D-galactose and hydrolysis of gelatin, protein, starch. The strains contained iso-$C_{14:0}$ (25.93%), iso-$C_{15:0}$ (10.13%), anteiso-$C_{15:0}$ (19.29%) and iso-$C_{16:0}$ (20.35%) as major fatty acids and MK-9 (H4), MK-9 (H6), and MK-9 (H8) as the isoprenoid quinone. Strain JR-24 was suggested new species of genus Streptomyces by nearest neighbors of genotypic relationships and phenotypic characterization. This study was important to microbial resources investigation for environment-friendly agriculture.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.212-219
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• 2016

Forty-nine pigments were extracted from the collections of 106 pigment producing bacteria from the plant rhizosphere soil. Antibacterial activity test was performed in the subjects of the extracted pigments with plant pathogenic bacteria including Xanthomonas axonopodis and Xanthomonas campestris, and with plant pathogenic fungi including Botrytis cinerea, Colletotrichum acutatum, and Fusarium oxysporum. The yellow pigment by Chryseobacterium sp. RBR9 and the red pigment by of Methylobacterium sp. RI13 showed the antibacterial activities against Xanthomonas axonopodis and Xanthomonas campestris. The violet pigment by Collimonas sp. DEC-B5 showed the antibacterial activity as well as the antifungal activities against Botrytis cinerea and Fusarium oxysporum. Especially, the violet pigment inhibited the growth of Botrytis cinerea more than 65% at MIC $20{\mu}M$. Upon the HPLC analysis result for the isolation of pigment with antifungal activity, violacein (91.6%) and deoxyviolacein (8.4%) were isolated for the pigment by Collimonas sp. DEC-B5. The production amount of the pigment was increased more than 10 times higher when D-mannitol 1.5% and yeast extract 0.2% were added as the nitrogen source to SCB medium. This study suggests that produced violacein by Collimonas sp. DEC-B5 will be effective to control strawberry gray-mold rot fungi by its preventive activity.