• Journal of Microbiology
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• 제33권4호
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• pp.344-349
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• 1995

The alkalophilic bacterium, Xanthomonas sp. JK311, producing extracellular proteases, was isolated from soil. Xanthomonas sp. JK311 produced five extracellular proteases that are all metalloproteases. Four of them were resistant against 1% SDS. Chromosomal DNA of the Xanthomonas sp. JK311 was digested with BamHI and cloned into PUC19. Among E. coli strain HB101 transformants, a clone secreting the proteases was screened through halo formation on skim-milk agar plate and by Southern blot analysis. It had the recombinant plasmid pXEP-1 containing the 7.5 kb-BamHI DNA fragment and produced three extacellular proteases. Their protease properties corresponded to those of Xanthomonas sp. JK311.

• 한국식품영양과학회지
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• 제25권1호
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• pp.53-57
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• 1996

Xanthomonas sp. EPS-1으로부터 생산된 다당류 EPS-1 용액의 농도가 0.04(g/dl)일 때, 비점도는 0.137, 환원 점도는 3.425, 상대점도는 1.137, 고유점도는 3.209임을 알 수 있었다. 겉보기 점도는 온도상슴에 따라 낮아졌으나 다시 온도를 증가하였을때는 서서히 증가하였다. 열처리 후에도 물성은 거의 변화지 않았으며, 응집성은 좋지 않았으나 locust bean gum과의 혼합효과는 우수하였다.

• 한국미생물·생명공학회지
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• 제23권2호
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• pp.145-149
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• 1995

For the purpose of developing a new biodegradable detergent, we have isolated a gene encoding wide-range temperature applicable alkaline protease from Xanthomonas sp. YL-37 (Lee et al., 1994, Kor. J. Appl. Microbiol. Biotechnol.). An alkaline protease gene was isolated from the gene bank that was prepared from the chromosomal DNA of Xanthomonas sp. YL-37. From the results of agarose gel electrophoresis and a restriction enzyme mapping, a 2.7 kb DNA fragment containing the alkaline protease gene was inserted in the plasmid pUC9. Extracellular activity of a clone having alkaline protease gene was detected on SDS-polyacrylamide gel with activity staining assay. The molecular weight of alkaline protease was determined to be about 64 kDa from 11% SDS-PAGE analysis. Alkaline protease activity, produced from E. coli which harboring the plasmid, showed no difference at reaction temperature 20, 30 and 40$\circ$C, respectively. This result showed that alkaline protease produced from E. coli harboring the plasmid was apparently the same as that of Xanthomonas sp. YL-37.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.515-521
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• 1994

A bacterial strain, which showed the high protease activity at low temperature and the high tolerance for the surfactant, was isolated from soil and identified as Xanthomonas sp. YL-37. The optimal temperature, initial pH, and cultivation time for the production of the alkaline protease by Xanthomonas sp. YL-37 were 20$\circC , 11.0, and 84 hours, respectively. In the jar fermenter culture of Xanthomonas sp. YL-37, the alkaline protease activity was about 15,000 DU/ml/-broth after cultivating for 108 hours. The optimal pH and temperature for the protease activity were 70$\circC and 11.0, respectively. The protease was relatively stable at the pH range of 7.0~12.0 and at the temperatures below 50$\circC . The protease activity at 20$\circC was about the level of 40% of its activity at 70$\circC . The enzyme was suggested as a serine protease because the enzyme activity was inhibited by phenylmethane sulfonyl fluoride, a serine modifier.

• Applied Biological Chemistry
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• 제35권1호
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• pp.30-35
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• 1992

Polyvinyl alcohol(PVA)을 탄소원으로 이용할 수 있는 세균 J2W 균주와 J2Y균주를 토양으로 부터 분리하였다. 분리된 이들 균주는 각각 별도의 순수배양으로는 PVA를 이용할 수 없었으나 이들 균주를 혼합배양 하였을 경우는 PVA를 분해 이용할 수 있었으며, 또한 PVA의 중합도(중합도 500, 1500, 2000)에 관계없이 이용할 수 있었다. 이들 두 균주는 다른 PVA 이용 공생균주 Pseudomonas PW와 Pseudomonas G5Y와 재구성하여 혼합배양 하였을 때 J2Y균주와 Pseudomonas PW, J2W 균주와 Pseudomonas G5Y 균주와의 혼합배양에서는 PVA를 이용할 수 있었다. 이들 두 균주는 동정 결과 J2W균주는 Pseudomons pseudomallei 근연균으로, J2Y는 Xanthomonas campestris 근연균으로 동정되었다.

• Applied Biological Chemistry
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• 제41권2호
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• pp.125-129
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• 1998

한국 토양에서 분리된 Xanthomonas sp.는 Candida albicans에 대한 용균성을 나타내며 분비효소로서 chitinase를 분비하는 것으로 사료되었다. 특히 chitinase활성은 chitin배지에서 배양했을 때 3일 배양에서 최대치를 나타내었다. 이러한 특성이 있는 Xanthomonas의 chitinase 유전자를 cloning하기 위하여 cosmid vector를 이용한 genomic library를 작성하였으며, 다른 박테리아 chitinase 유전자와 homology를 가진 지역의 DNA sequence를 oligonucleotide로 합성하여 probe로 사용한 결과 4개의 독립된 positive clone을 cloning 하였다. 이중 pXCHl(1.2 kb insert) 이라고 명명한 clone에 대해 해석한 결과 이 크론의 전사산물은 chitin 배지에서만 유도됨을 확인하였으며 대장균 발현 vector를 이용한 이 유전자의 대장균에서의 발현에 대한 실험의 결과 약 35 kDa의 단백질을 생산하는 것으로 확인하였다. 또한 이 산물의 chitinase활성을 측정한 결과 유전자가 포함되지 않은 산물에 비해 약 10배의 활성을 나타내어 이 유전자를 Xanthomonas sp.의 chitinase유전자임을 증명하였다.

• 미생물학회지
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• 제52권2호
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• pp.212-219
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• 2016

식물 근권 토양으로부터 색소생성 균주 106균주를 수집하여 색소 생성능이 우수한 균주로부터 노란색(33개), 주황색(12개), 분홍색, 빨간색, 갈색 그리고 보라색 총 49개의 세균색소를 추출하였다. 식물병원균에 대한 항균활성능이 우수한 색소를 선발하기 위하여 고추점무늬병원균(Xanthomonas axonopodis), 흑마병원균(Xanthomonas campestris)과 딸기잿빛곰팡이병원균(Botrytis cinerea), 고추탄저병원균(Colletotrichum acutatum), 그리고 시들음병원균(Fusarium oxysporum)을 대상으로 항균활성 검정을 수행하였다. 색소생성 Chryseobacterium sp. RBR9 균주가 생산하는 노란색 색소와 Methylobacterium sp. RI13 균주가 생산하는 빨간색 색소는 X. axonopodis와 X. campestris에 항세균 활성을 나타내었다. 차나무 토양으로부터 분리된 Collimonas sp. DEC-B5가 생산하는 보라색 색소는 항세균 활성과 더불어 B. cinerea와 Colletotrichum acutatum에 항진균활성을 나타내었다. 특히, 보라색 색소는 최소저해 농도 $20{\mu}M$에서 B. cinerea를 65% 이상 생육 저해하였다. 항진균활성 보라색 색소를 HPLC 분석한 결과, violacein (91.6%)와 deoxyviolacein(8.4%)으로 동정되었다. 보라색 색소 violacein의 생산량은 SCB 배지에서 $43.2{\mu}M$이었고 D-mannitol 1.5%, yeast extract 0.2%를 첨가한 경우 $431.6{\mu}M$로 약 10배 높은 색소 생성량을 나타내었다. 본 연구에서 분리된 Collimonas sp. DEC-B5가 생산하는 violacein 색소는 딸기잿빛곰팡이병원균 방제제로 활용 가능성이 확인되었다.

• 식물병과 농업
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• 제5권1호
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• pp.41-45
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• 1999

Bacterial population densities on soybean pods from Chungnam province ranges 105~106 CFU/$\textrm{cm}^2$, whereas those of bacteria causing sprout rot ranged 0~103 CFU/$\textrm{cm}^2$. Erwinia chrysanthemi, Xanthomonas campestris pv. glycines, Staphylococcus sp., and Micrococcus sp. were identified as pathogenic bacteria causing soybean sprout rot. The population density of X. campestris pv. glycines was higher than those of other bacteria.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.269-274
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• 1995

For the screening of a new functional exopolysaccharide, sugar composition and rheological properties of exopolysaccharide produced from Xanthomonas sp. EPS-1 were investigated. The average molecular weight of exopolysaccharide was determined to be approximately 2.l $\times$ 10$^{6}$ dalton. The new exopolysaccharide EPS-1 was composed of mannose, glucose, galactose and gluco- samine. IR analysis showed that the exopolysaccharide EPS-1 was assumed to be polymer with carbohydrates. NMR analysis showed that exopolysaccharide EPS-1 was presumed to be 4 units of sugar and trace of CH$_{3}$ group. Exopolysaccharide EPS-1 solution showed a characteristic of non-Newtonian fluid properties. At the concentration of 1.0%, the consistency index and the flow behavior index were shown at 10.8352 poise-sec and 0.4419, respectively. All dispersions were pseudoplastic fluids described accurately by Power-law model. Exopolysaccharide EPS-1 was highly viscous at low concentration, with good stability over a wide range of pH 5 to 13. The excellent compatibility of exopolysaccharide EPS-1 was represented with salts such as sodium chloride.

• 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.