• Korean Journal of Plant Resources
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• v.12 no.2
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• pp.152-160
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• 1999

Bacterial population density on soybean leaves was $10^2~10^5CFU/cm^2$. Bacterial population density was increased by progress of plant growth stage. Population density of soybean sprout rotting bacteria on soybean leaves was $0~10^3CFU/cm^2$. Population density of soybean sprouts rotting bacteria was related to cultivating area, but not related to plant growth stage. Cultivar and population density of soybean sprout rotting bacteria were less corelated, and varied by plant growth stages and plant parts. Erwina cypripedii, E. carotovora subsp. carotovora, Xanthomonas campestris pv. glycines, Staphylococcus sp., and Micrococcus sp. were identified as pathogenic bacteria causing soybean sprout rot. In generally population density of E. cypripedii, E. carotovora subsp. carotovora, Micrococcus sp., and X. campestris pv. glycines were high.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.71-75
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• 1990

The isolates biodigrading crude oil were examined to characterize thier properties. Isolates which were identified as Acinetobacter lwoffii G1, Klebsiella pneumoniae L25, Pseudomonas maltophilia N246, Xanthomonas campestris M12, and Xanthomonas sp. M28. The optimum concentration of crude oil was 0.15% for the bacterial growth. X. campestris M12, Xanthomonas sp. M28, and K. penumoniae L25 showed the maximal growth at the concentration of 3.5% sodium chloride, indicating that they were derived from sea water. Among the isolates, X. campestris M12, Xanthomonas sp. M28 specially utilized hexadecane and octane, and P. maltophilia N246 utilized octane with optimum concentration of 0.2-0.3% as sole carbon source. The utilization of components of saturate fraction by K. pneumoniae L25 was examined by gas-liquid chromatography. The short-chain saturates are used before the long chain ones although they almost disappear within 8 days of incubation at $30^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.82-87
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• 1991

Xanthomonns curnpestris M12, Xunthornonas sp. M28, Acinetuhucter Iwofz GI, and Klebsiella pneumoniae L25, Pseudomonas rnaltophiliu N246 were screened to increase the ability for crude oil utilization. All of these could utilize hexadecane and octane with the exception of N246 strain for only octane biodegradation. Thus N246, M12, and M28, strains were specially examined for octane oxidation. Octane biodegradation by three strains showed the optimal conditions at $30^{\circ}C$, pH 7.0~9.0, and 0.2~0.3% octane concentration as a substrate. It was found that P. multofihila N246 and X. curnpestns M12 had plasmid and the cured plasmid from N246 strain lost octane uitilization. Therefore, it was confirmed that certain genes for octane utilization were Iocated on OCT plasmid in N246 strain. The size of OCT plasmid in N246 strain was 118 kb. The N246 strain was resistant to ampicillin.

• The Korean Journal of Pesticide Science
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• v.13 no.1
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• pp.45-53
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• 2009

An antagonistic bacterial strain KLF01 was isolated from rhizosphere of tomato and identified to be Lactobacillus sp. by biochemical and genetic analysis. This strain showed antagonism against the used plant pathogenic bacteria like Ralstonia solanacearum, (bacterial wilt), Xanthomonas axonopodis pv. citri, (Citrus canker), Xanthomonas campestris pv. vesicatoria (Bacterial spot), Eriwinia pyrifoliae (Shoot-blight) and Eriwinia carotovora subsp. carotovora group (Potato scab) through agar well diffusion method. In planta test done by drench application of strain KLF01 $(4{\times}10^8 cfu/ml)$ into the experimental plot containing tomato (Solanum lycopersicum L.) cultivar 'Lokkusanmaru' and red pepper (Capsicum annuum L.) cultivar 'Buja' plants, in pot test post-inoculated with the plant pathogenic bacteria, R. solanacearum significantly reduced the disease severity, compared to the non-treated plants.

• Journal of Microbiology
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• v.33 no.2
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• pp.115-119
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• 1995

The alkaline protease of Xanthomonas sp. YL-37 has been purified, and the properties of the enzyme investigated. The alkaline protease of Xanthomonas sp. YL-37 was purified form crude enzyme by ammonium sulfate fractionation, CM-cellulose ion exchange chromatography, and Sephadex G-100 gel filtration. Through the series of chromatographies, the enzyme was purified to homogenecity with specific activity of 4.23 fold higher than that of the crude broth. The molecular weight of the purified protease has been estimated to be 62 KDa on SDS-polyacrylamide gel electrophoresis. The optimal pH and temperature for alkaline protease activity were 11.0 and 50.deg.C, respectively. The enzyme was stable between pH 5.0 and 10.0 and up to 50.deg.C. Enzyme activity was lost up to 50% on heating at 70.deg.C for 30 minutes. The activity of alkaline protease was inhibited by Cu$\^$2+/, Zn$\^$2+/, Hg$\^$2+/, PMSF, and activated by Mn$\^$2+/ and Ca$\^$2+/. The $K_{m}$ value for casein as a substrate was 4.0 mg/ml.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.587-589
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• 2000

The production of inulooligosaccharides from inulin by a dual endoinulinase system of Pseudomonas sp and Xanthomonas sp. was investigated the optimum conditions for a dual endoinulinase reaction were as follows : pH,5.8; temperature, $50^{\circ}C$; substrate concentration, 50 g/l; enzyme ratio, 3:1 as Xanthomonas endoinulinase to Pseudomonas endoinulinase. Under optimum conditions, the maximum yield of oligosaccharides was 90.5% in total sugar basis by dual endoinulinase system

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.427-434
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• 1998

An alkaline protease was 4-fold purified, yielding 2.3% of recovery by ammonium sulfate precipitation, CM-cellulose column chromatography and Sephadex G-100 column chromatography. The purified enzyme was estimated to be monomeric with molecular weight of about 62,000 from polyacrylamide gel eletrophoresis (PAGE) and sodiumdodecylsulfate polyacrylamide gel electrophoresis (SDS-FAGE). The optimal pH and temperature of the alkaline pretense activity were 11.0 and 50$^{\circ}C$, respectively, exhibiting high stability at pH value from 6.0 to 11.0 at 50$^{\circ}C$ for 30 minute. The alkaline pretense was activated by MnSO$_4$, CaCl$_2$, and was inhibited by CuSO$_4$, ZnSO$_4$, HgCl$_2$, EDTA and EGTA. Also, the enzyme was found to be a metaloenzyme requiring Mn$\^$2+/ as cofactor. The NH$_2$-terminal amino acid of alkaline protease was alanine. The Km and Vmax values of this enzyme for casein was 4.0 mg/$m\ell$ and 5,500 unit/$m\ell$, respectively.

• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.998-1000
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• 2003

This study was carried out to elucidate the mode of bacteriostatic property of xanthostatin (XS), a novel depsipeptide antibiotic with an N-acetylglycine side chain and selective antimicrobial activity against Xanthomonas spp. Two biotransformed XSs were isolated by the treatment of XS with the cell lysate of Xanthomonas campestris pv. citri, a solvent partition, preparative TLC, and HPLC. Structure determination of those two biotransformed XSs demonstrated deletion of the N-acetylglycine side chain. Noteworthily, they showed no antimicrobial activity against Xanthomonas spp. This result suggests that the N-acetylglycine side chain plays a critical role in the antimicrobial activity of XS, and that the bacteriostatic property of XS is due to susceptibility of the ester bond between the hexadepsipeptide nucleus and the N-acetylglycine side chain to hydrolytic enzyme(s) produced by Xanthomonas spp.

• Research in Plant Disease
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• v.10 no.2
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• pp.94-99
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• 2004

'Shiranuhi' citrus cultivar bred by crossing 'Kiyomi' tangor and 'Nakano No.3' ponkan is cultivated in polyethylene film house, and the number of cultivating farmers is rapidly increasing in recent years. Recently, some diseases are taking place on 'Shiranuhi' fruit in some orchards, and were to be big problem in some case. It was surveyed that six diseases were mainly taken place in 'Shiranuhi' cultivating orchards in Jeju Island. They were Phytophthora citrophthora, Alternaria sp., Penicillium digitatum, Botrytis cinerea, Diaporthe citri and Xanthomonas axonopodis pv. citri.

• 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.