• 한국식물병리학회지
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• 제11권1호
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• pp.53-60
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• 1995

Inoculation with the compatible strain Ds 1 of Xanthomonas campestris pv. vesicatoria caused brownish ad water-soaked lesions, but incompatible strain Bv5-4a produced hypersensitive symptoms with local necrosis on tomato (cv. Kwangyang) leaves. Bacterial populations of the compatible strains Ds 1 propagated more greatly than the incompatible strain Bv5-4a at the frist onset, but no differences were observed 5 days after inoculation. The bacterial infection induced the synthesis and accumulation of soluble proteins in tomato leaves, especially in the incompatible interaction. Native-polyacrylamide gel electrophoresis distinguished the soluble proteins in the tomato leaves infected by the compatible or incompatible strains. A protein of low molecular weight occurred only in the incompatible interaction. Some pathogenesis-related (PR) proteins, especially the 15, 18, 23, 26 and 54 kDa proteins, were detected only in the infected tomato leaves. In the two-dimensional electrophoresis, some proteins with different molecular weights (Mr. 21∼29 kDa) and the pI 8∼9 appeared more distinctly only in the incompatible interaction. These data suggest that the de novo synthesis of some PR proteins in tomato may be significant in defense against X. c. pv. vesicatoria.

• 한국식물병리학회지
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• 제14권5호
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• pp.376-381
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• 1998

Xanthomonas campestris pv. glycines 8ra causes bacterial pustule disease on susceptible soybean leaves and produces a bacteriocin, named glycinecin, against related bacteria such as Xanthomonas campestris pv. vesicatoria. The antimicrobial activity of the glycinecin was effective to most tested Xanthomonas species. X. c. pv. glycines 8ra was able to produce the glycinecin in liquid media as well as solid media. Maximal productivity of glycinecin was obtained at 3$0^{\circ}C$ in the early stationary phase of growth of the X. c. pv. glycines 8ra. The production of glycinecin was not dependent on the initial inoculum level but on cell density. Glycinecin was very sensitive to proteolytic enzymes such as trypsin and proteinase K but resistant to DNase and RNase. The culture supernatant of X. c. pv. glycines 8ra retained some of its antimicrobial activity after 15 min at 6$0^{\circ}C$. It is stable at wide range of pH. The glycinecin showed the bactericidal activity after the adsorption of the glycinecin to the sensitive bacterial cell.

• 한국식물병리학회지
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• 제10권1호
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• pp.13-17
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• 1994

A semiselective agar medium (XCO) was developed for the isolation of bacterial blight pathogen, Xanthomonas campestris pv. oryzae, from rice seed. The medium contained yeast extract 1.0 g, peptone 2.0 g, sucrose 5.0 g, sodium glutamate 1.0 g, FeSO4.7H2O 0.05 g, Fe.EDTA 1 mg, cephalexin 20 mg, Evan blue (0.1%) 1.5 ml, bromcresol purple (0.1%) 2.5ml, cycloheximide 100 mg and agar 15.0 g per liter. Colonies of X. c. pv. oryzae were 4~5 mm in diameter, smooth, round, blue (darker center) and convex after 6 days incubation at 28$^{\circ}C$. The recovery of 6 isolates of X. c. pv. oryzae on the XOC medium ranged from 81% to 120% (mean 98.2%) in comparison to Wakimoto's medium. The number of saprophytic bacteria from 10 rice seed lots on XCO medium was reduced to 70.4% of that on Wakimoto's medium. The recovery of X. c. pv. oryzae added to rice seed on XOC medium ranged from 67% to 87% (mean 75.6%) of that on Wakimoto's medium.

• 한국환경농학회지
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• 제40권1호
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• pp.20-32
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• 2021

BACKGROUND: Bacterial shot hole of stone fruits is a seriuos plant disease caused by Xanthomonas arboricola pv. pruni (Xap). Techniques to control the disease are required. In this study, microorganisms with antibacterial activity were isolated to develop as a microbial agent against the bacterial shot hole. METHODS AND RESULTS: An isolate with the strongest activity among the isolates was identified as Streptomyces avidinii based on 16S rRNA gene sequence analysis and designated Streptomyces sp. J46. J46 showed suppression of bacterial leaf spot with a control value of 90% at 10 times-diluted cell free supernatant. To investigate antibacterial metabolites produced by J46, the supernatant of J46 was extracted with organic solvents, and the extracts were subjected to chromatography works. Antibacterial metabolites were not extractable with organic solvents. Both reverse and normal phase techniques were not successful because the metabolites were extremely water soluble. The antibacterial metabolites were not volatiles but protein compounds based on hydrolysis enzyme treatment. CONCLUSION: Our study suggests that Streptomyces sp. J46 may be a potential as an microbial agent against bacterial shot hole. Further study to identify the metabolites is required in more detail.

• The Plant Pathology Journal
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• 제40권2호
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• pp.225-232
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• 2024

The microbiomes of two important rice cultivars in Vietnam which differ by their susceptibility to the bacterial leaf blight (BLB) disease were analyzed through 16S rRNA amplicon technology. A higher number of operational taxonomic units and alpha-diversity indices were shown in the BLB-resistant LA cultivar than in the BLB-susceptible TB cultivar. The BLB pathogen Xanthomonas was scantly found (0.003%) in the LA cultivar, whereas was in a significantly higher ratio in the TB cultivar (1.82%), reflecting the susceptibility to BLB of these cultivars. Of special interest was the genus Acholeplasma presented in the BLB-resistant LA cultivar at a high relative abundance (22.32%), however, was minor in the BLB-sensitive TB cultivar (0.09%), raising a question about its roles in controlling the Xanthomonas low in the LA cultivar. It is proposed that Acholeplasma once entered the host plant would hamper other phytopathogens, i.e. Xanthomonas, by yet unknown mechanisms, of which the triggering of the host plants to produce secondary metabolites against pathogens could be a testable hypothesis.

• 한국식물병리학회지
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• 제13권3호
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• pp.172-178
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• 1997

십자화과 작물에 발생하는 검은썩음병(Black rot or Black vein of crucifer)의 병원성 세균인 Xanthomonas campestris pv. crucifer)의 병원성 세균인 Xanthomonas campestris pv. campestris를 분리, 동정하고 병원성을 검정하였다. 이 X. c. pv. campestris 는 3가지 종의 Chinese cabbage에 병원성을 나타내었고, 병원성과 관련된 특성을 결정하기 위하여 Tn5 mutagenesis를 실시 cellulase negative mutant를 선발하여 병원성 검정하였다. 선발된 cellulase negative mutant를 배추에 분무 접종하여 광학 현미경과 전자현미경으로 관찰한 결과 cellulase negative mutant는 wild type와 함께 기공표면과 기공하부조직에서 정착하였지만 그 밀도는 낮았다. 반면 접종 24시간 이후 wild type은 기공표면과 기공하부조직이 lysis되기 시작하여 48시간 이후에는 병원성의 진전으로 보다 많이 lysis되었다. 6일 후, wild type은 cellulase활성에 의해 식물체 조직에서 높은 증식력을 보이며 조직을 lysis 시키고 또한 조직 깊숙이 침입, 정착하는 것을 관찰하였다. 이 결과로 X. c. pv.c campestris의 cellulase는 병원성에 관여하는 중요한 요인으로 생각된다.

• 미생물학회지
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• 제28권1호
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• pp.71-75
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• 1990

한국 해안으로부터 우수 원유분해능 균주를 분리동정하여 그 특성을 관찰하였다. 이들 분리균주 중 우수 균주로는 Acinetobacter twoffii G1, Klebsiella pneumoniae L25, Pseudomonas maltophilia N246이 동정되었다. 이들 균주의 생장은 0.15%의 원유 농도와 3.5% sodium chloride에서 최대의 생장을 보여주었다. 이들 균주 중 X. campestris M12와 Xanthomonas sp. M28은 특별히 hexadecane과 octane을 그리고 P. maltophilia N246은 octane 을 탄소원으로 0.2-0.3%의 농도에서 최대로 분해하였다. K. pneumoniae L25에 의한 crude oil의 경Al적인 분해과정을 gas-liquid chromatography로 분석하였으며, 그 결과 긴 사슬의 alkane 보다 C14 이하의 짧은 사슬의 alkane을 보다 쉽게 이용하였으며 $30^{\circ}C$에서 8일간 배양시에 거의 모두 이용되었다.

• The Plant Pathology Journal
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• 제27권3호
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• pp.207-224
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• 2011

Diseases caused by plant pathogenic bacteria constitute an emerging threat to global food security. Xanthomonas is a large genus of Gram-negative bacteria that cause disease in several host plants leading to considerable losses in productivity and quality of harvests. Despite the ranges of controlling techniques available, the microbiological safety of economically important crops and crop plants including fruits and vegetables continues to be a major concern to the agriculture industry. On the other hand, many of the currently available antimicrobial agents for agriculture are highly toxic, non-biodegradable and cause extended environmental pollution. Besides, the use of antibiotics has provoked an increased resistance among the bacterial pathogens and their pathovars. Thus, novel efficient and safe remedies for controlling plant bacterial diseases are necessary. There has been an increasing interest worldwide on therapeutic values of natural products such as essential oils, hence the purpose of this review is to provide an overview of the published data on the antibacterial efficacy of essential oils that could be considered suitable for application in agriculture as biocontrol measures against plant pathogenic bacteria of Xanthomonas species. The current knowledge on the use of essential oils to control Xanthomonas bacteria in vitro and in vivo models has been discussed. A brief description on the legal aspects on the use of essential oils against bacterial pathogens has also been presented. Through this review, a mode of antibacterial action of essential oils along with their chemical nature and the area for future research have been thoroughly discussed.

• 유기물자원화
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• 제12권1호
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• pp.67-74
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• 2004

난지도 하수처리장내 슬러지로부터 페놀을 유일한 탄소 및 에너지원으로 이용하는 세균을 분리하여 그 특성을 조사하고 동정하였다. 본 세균은 그람 음성 구균으로 운동성을 가지며 페놀의 농도가 0.05%, 0.10%, 0.15%인 배지에서 성장을 보였으며, BBL Test를 실시한 결과 유사성을 가진 세균이 나타나지 않았다. 세균의 계통분류학적 분석을 위하여 세균의 염색체로부터 16s rDNA를 클로닝한 후 DNA 염기서열을 파악하고 이를 비교 및 분석한 결과 본 세균은 Proteobacteria의 Gamma (${\gamma}$) Subdivision에 속한 Xanthomonas Group의 Stenotrophomonas maltophilia strain과 99%의 유사성을 보이는 것으로 나타났다. 또한 Nitrogen-Fixing bacterium MAGDE3, Pseudomonas cissicola strain과는 98%의 상동성을, Stenotrophomonas sp. LMG 198, Xanthomonas cucurbitae과는 97%의 상동성을 보였다.

• 한국미생물·생명공학회지
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• 제19권1호
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• pp.82-87
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• 1991

원유 분해세균에 의한 원유 분해능을 조사한 결과, Xanthomonas camperstris M12, Xanthomonas sp. M28, Acintobacter lwoffi G1, Klebsiella pneumoniae L25, 그리고 Pseudomonas maltophilia N246 등의 순서로 나타났다. Xanthomonas maltophilia M12, Xanthomonas sp. M28, 그리고 Pseudomonas maltophilia N246 균주 모두 pctane 분해시의 온도는 $30^{\circ}C$에서 최적이었으며, 최적 pH는 X.camperstris M12와 Xanthomonas sp. M28이 7.0-7.5 이었고, P.maltophilia N246이 7.5-9.0이었다. N246 균주의 최적 NaCl농도는 3.0-3.5 이었다. P.maltophilia N246와 X.campestris M12는 모두 플라스미드를 갖고 있음을 확인하였고, N246 균주로 부터 플라스미드를 제거하였을 경우 octane 분해능이 소실되었으므로 이 플라스미드 위에 octane 분해 유전자가 있음이 확인되었다. 이 균주이 OTC 플라스미드의 크기는 118kb이었다. 또한, N246 균주는 ampicillin 항생제에 내성을 나타내었다.