• Research in Plant Disease
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• v.10 no.1
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• pp.8-12
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• 2004

The diseased ginseng plants, their trunks fall down anil roots rot, were observed in ginseng cultivation field at Bongwha, Kyungbuk. Inoculation of the bacterium isolated from root rot lesion induced a range of symptoms on leaves, trunks and roots; The bacterium caused wilting with chlorosis and black discoloration on leaves, empty of inside trunks and rot on roots. The bacterium was identified as Serritia liquefaciens based on the morphologcal and physiological characteristics. This is the first report in Korea on roots rot of ginseng occurred by S. liquefaciens.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.180-186
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• 2007

The biocontrol agent, Serratia plymuthica A21-4, has been developed for controlling pepper Phytophthora blight. Serratia plymuthica A21-4 strongly inhibits the mycelial growth, zoospore formation, and cyst germination of Phytophthora capsici in vitro. The application of a cell suspension of strain A21-4 to pepper plants in pot experiments and in greenhouse successfully controlled the disease. The bacteria produced a potent antifungal substance which was a key factor in the suppression of Phytophthora capsici. The most active chemical com-pound was isolated and purified by antifungal activity-guided fractionation. The chemical structure was identified as a chlorinated macrolide $(C_{23}H_{31}O_8Cl)$ by spectroscopic (UV, IR, MS, and NMR) data, and was named macrocyclic lactone A21-4. The active compound significantly inhibited the formation of zoosporangia and zoospore and germination of cyst of P. capsici at concentrations lower than $0.0625{\mu}g/ml$. The effective concentrations of the macrocyclic lactone A21-4 for $ED_{50}$ of mycelial growth inhibition were $0.25{\mu}g/ml,\;0.25{\mu}g/ml,\;0.30{\mu}g/ml \;and\;0.75{\mu}g/ml$ against P. capsici, Pythium ultimum, Sclerotinia sclerotiorum and Botrytis cinerea, respectively.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.129-135
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• 1992

A chitinase gene of Serratia marcescens ATCC 27117 was cloned and expressed in Escherichiu di. A genomic library of S, marcescens was constructed with pUC 19 and screened using the swollen chitin agar plate for chitinolytic clones. A positive clone showing chitinclearance contains a recombinant pCHI 89, composed of 8.9 Kb chromosomal DNA fragment and pUC 19. Plasmid pCHI 89 produced 58 KD chitinase in E. coli, which was coincided with one of five extracellular chitinases produced by S. nzarccscens. Restriction endonuclease cleavage sites of the 8.9 Kb insert DNA fragment were mapped. E. coli JM109 harboring pCHI 89 inhibits the growth of a plant pathogenic fungus, Fusarium oxysporum.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.950-957
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• 2010

Serratiopeptidase (SRP), a 50 kDa metalloprotease produced from Serratia marcescens species, is a drug with potent anti-inflammatory property. In this study, a powerful statistical design, evolutionary operation (EVOP), was applied to optimize the media composition for SRP production in shake-flask culture of Serratia marcescens NRRL B-23112. Initially, factors such as inoculum size, initial pH, carbon source, and organic nitrogen source were optimized using one factor at a time. The most significant medium components affecting the production of SRP were identified as maltose, soybean meal, and $K_2HPO_4$. The SRP so produced was not found to be dependent on whey protein, but rather was notably induced by most of the organic nitrogen sources used in the study and free from other concomitant protease contaminant, as revealed by protease inhibition study. In addition, experiments were performed using different sets of EVOP design with each factor varied at three levels. The experimental data were analyzed with a standard set of statistical formula. The EVOP-optimized medium, with maltose 4.5%, soybean meal 6.5%, $K_2HPO_4$ 0.8%, and NaCl 0.5% (w/v), gave a SRP production of 7,333 EU/ml, which was 17-fold higher than the unoptimized media. The application of EVOP resulted in significant enhancement of SRP production.

• The Korean Journal of Food And Nutrition
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• v.12 no.1
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• pp.43-49
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• 1999

The effects of purine catabolites in growth media on the Serratia marcescens purine nucleoside phos-phorylase activity were examined. The enzyme activity was decreased above 60% by guanosine(5 to 15mM). The enzyme activity was not affected at low concentration of inosine (0.1∼1mM). The en-zyme activity was decreased approximately by 40∼50% in the presence of high concentrations of aden-osine hypoxanthine and xanthine (5∼15mM) but was not affected at low concentration of adenosine hypoxanthine and xanthine (0.1∼0.5mM). However the enzyme activity was increase by 20% with low concentrations of uric acid(0.5mN). but was decreased by 80% with high concentrations of same purine catabolite (15mM). Also the enxzyme activity was increased by 20% with low concentrations of glyoxylate (0.5mM) final degradative product of uric acid but was decreased by 30∼50% with high con-centrations of glyoxylate (3∼15mM). The enzyme activity was decreased approximately by 20% by the simultaneous addition of inosine hypoxanthine and uricacid at 5mM each whereas it was increased by 22 and 33% by the combination of inosine and uric acid three purine catabolites at 0.5mM respectively These data suggest that S. marcescens purine nucleoside phosphorylase is positively regulated by a glyox-ylate concentration and then may play a regulatory role in a purine catabolism.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.475-479
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• 1997

The effects of amino acids and metabolites in growth media on the biosynthesis of prodigiosin from Serratia marcescens ATCC 25419 were examined. The prodigiosin synthesis was decreased approximately by 50 to 80% by several amino acids and metabolites tested. The prodigiosin synthesis was increased approximately by 20 to 40% by a low concentration of glyoxylate(1 to 3mM) and outstandingly increased by 122% at 5mM concentration under anaerobic condition. However, the prodigiosin synthesis was decreased approximately by 50 to 90% at a high concentration(20 to 30mM) under anaerobic condition. The prodigiosin was not synthesized by pyruvate and $\alpha$-ketobutyrate under aerobic and anaerobic condition, with addition to glyoxylate under aerobic condition, among the range from 0.5 to 30mM, while the cell growth under anaerobic condition was decreased distinctly by a high concentration(20mM above) of glyoxylate. These data suggest that the growth and prodigiosin of S. marcescens is positively regulated by a low concentration of glyoxylate (1-5mM), but repressed by a high concentration of glyoxylate(20mM above) unlike pyruvate and $\alpha$-ketobutyrate.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.693-698
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• 1992

The resistant effect of several heavy metal ions to Serratia marcescens strain P was studied by the method of minimal inhibitory concentration(MIC), and testing for their metal biosorption. S. marcescens strain P showed a good survival in the presence of high concentrations of some metal ions, namely cadmium, lead, iron, magnesium, and manganese. Copper had the most inhibitory effect among tested. The MIC value was ranged from 0.79 to 1.58 mM. Cells of S. marcescens strain P exhibit an abnormally long lag phase when incubated in high concentrations of zinc and cadmium. Pigment production was reduced by zinc and cadmium, but enhanced by lead and iron. S. marcescens strain P was resistant to ampicillin, tetracycline, cefamandole and chloramphenicol with minimal inhibitory concentration of 128 $\mu$g/ml, 32 $\mu$g/ml, 256 $\mu$g/ml, and 8 $\mu$g/ml, respectively. The kinetics study of biosorptive uptake by S. marcescens strain P revealed that 16.59% of cadmium and 35.38% of lead were eliminated from the media.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.511-518
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• 1992

We subcloned a 58 KD chitinase gene of Serratia marcescens into Escherichia coli and investigated the expression and secretion of the chitinase. Chitinase was produced in E. coli by using its own promoter but the levels of enzyme were very low, less than 5 mU/m$\ell$. However, by the combined action of the chitinase and lac promoters, the chitinase activity increased up to about 80 mU/m$\ell$. The most of the chitinase produced in E. coli was localized in periplasm and the small amounts were observed in cytosol and culture medium. Intracellular chitinase activities increased in proportion to the growth of E. coli up to the early stationary phase but rapidly decreased thereafter, which was assumed to be degradation of the chitinase by E. coli proteolytic enzymes.

• Food Science of Animal Resources
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• v.34 no.4
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• pp.543-551
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• 2014

The aim of this study was to evaluate the effect of proteolytic (Serratia liquefaciens, match %: 99.39) or lipolytic (Acinetobacter genomospecies 10, match %: 99.90) psychrotrophic bacteria (bacterial counts, analysis of free fatty acids (FFA) and analysis of free amino acids) on the microbial and chemical properties (yogurt composition), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of yogurt during storage. Yogurts were prepared with raw milk preinoculated with each psychrotrophic bacteria. The total solid, fat, and protein content were not affected by preinoculation, but the pH of yogurt preinoculated with psychrotrophic bacteria was higher than in control. There was a dramatic increase in short chain free fatty acids among FFA in yogurt with Acinetobacter genomospecies 10. For 14 d of cold storage condition, SCFFA was 25.3 mg/kg to 34.4 mg/kg (1.36 times increased), MCFFA was 20.4 mg/kg to 25.7 mg/kg (1.26 times increased), and LCFFA was 240.2 mg/kg to 322.8 mg/kg (1.34 times increased). Serratia liquefaciens (match %: 99.39) in yogurt caused a greater accumulation of free amino acids (FAA), especially bitter peptides such as leucine, valine, arginine, and tyrosine, but SDS-PAGE showed that the inoculation of Serratia liquefaciens did not affect the degree of casein degradation during storage. Taken together, the excessive peptides and FFA in yogurt generated from psychrotrophic bacteria could develop off-flavors that degrade the quality of commercial yogurt products.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.330-337
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• 1993

A bacterium, pathogenic to Nilaparvata lugens Stal. causing high mortality in 3~5 days, were selected and identified as Serratuz marcescens biotype A2a which is not a nosocomlally infective strain. In order to determine the characters of Serratia marcesce'1lS associated with insect pathogenicity, Tn5 mutagenesis was carried out by conjugating with E. coli pJB4J1. Transconjugants were plate-assayed for missing chitinase, protease and DNase activity. A protease negative mutant was selected for missing JOseet pathogenicity. SEM and TEM revealed the presence of bacterial cells in the epithelial tissue of inner abdomal tissue of the hypodermic layer of abdomen. Such a colonization was limmited to the subjacent tissue inside the intacL cuticular epidermis. These observation supported our result of pathogenicity tests of transconjugants.