• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.301-307
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• 2006

A ligniolytic bacterial strain was isolated from the digestive tract of a red dragonfly, Sympetrum dopressiusculum. It was identified as a Serratia marcescens HY-5 by 16S rDNA sequence analysis and physiological and biochemical analysis. The isolated strain showed proportional increase of ligninolytic activity to the cell growth in the culture media which include lignin compounds. It showed about 25-45% decomposition of lignin compound by 48 hr incubation especially, showed effective decomposition of monomer lignin compounds, vanillin and guaiacol, and a dimer, dealkaline lignin. PCR amplification of 16S rDNA followed by denaturing gradient gel electrophoresis analysis showed high density of S. marcescens HY-5 in the gut of the S. depressiusculum at both gut samples which collected at different site.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.227-232
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• 1990

S. marcescens cultured at $30^{\circ}C$ with vigorous shaking was shown to produce red-pigment, prodigiosin, in the senescent phase of growth. Also, it showed many hydrophobic characteristrics, which were tested by the adherence to noncharged surfaces of polystyrene dishes, a typical agent for the binding of hydrophobic cells and molecules. However, when the cell was cultured at $37^{\circ}C$, it no longer produced either red pigment or hydrophobic materials. Therefore, the bacteria cultured at $37^{\circ}C$ was completely washed-out from the polystyrene dishes at the copious washing step with tap water, in contrast to the cell cultured at $30^{\circ}C$ which was sticked onto the polystyrene dishes very tightly. The lipid compositions extracted from the S. marcescens cultured at $30^{\circ}C$ or $37^{\circ}C$ were very different from each other; the phospholipids, glycolipids and unidentified lipids were produced from the cell cultured at $30^{\circ}C$, whereas large amounts of serratamolide, amphipathic compound, were produced from the cell cultured at $37^{\circ}C$. The data suggest that the pronounced cell surface hydrophobicity of the S. marcescens is mediated by a combination of several surface factors that were affected by cultivation time and temperatures.

• Research in Plant Disease
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• v.15 no.2
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• pp.101-105
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• 2009

The biocontrol agent Serratia plymuthica A21-4 was selected and proved as an excellent inhibitor of Phytophthora blight of pepper through in vitro and in vivo experiments in previous studies. To enhance the colonizing density of S. plymuthica A21-4 on plant root and rhizosphere soil, some soil conditions might effect on the colonization of the bacteria were examined. The results obtained from the study indicated that the soils containing more sand were favorable to root colonization of S. plymuthica A21-4. Organic amendment such as 3% maize straw(w/w) was helpful to colonize the bacteria in root and soil. The soil temperature about $20^{\circ}C$, water content around 40%, and soil pH near to neutral or slightly acidic, were optimum condition for the colonization of S. plymuthica A21-4 in the rhizosphere soil and roots of pepper. In addition, existence of indigenous biotic entities was beneficial to the colonization of S. plymuthica A21-4.

• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.221-226
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• 2013

Degrees of hydrolysis by alkaline protease produced from Serratia marcescens S3-R1 is 3.95-6.30% of whey proteins during 5, 15, 30, 60, 90, 120,180, 240 min incubation at $40^{\circ}C$. Proteolytic pattern of the whey proteins showed that various low molecular weight peptides were generated during the incubation periods. The biological function of in Raw 264.7 cells treated with whey protein hydrolytic peptides, anti-inflammatory effect showed exhibit in the expression of pro-inflammatory cytokines such as TNF-${\alpha}$, IL-6, COX-2 and iNOS by PCR analysis. COX-2 and iNOS gene expression inhibited in Raw 264.7 cells on whey protein hydrolysates below 3,000 dalton. The protease from Serratia marcescens S3-R1 showed a potential in production of low molecular weight whey protein hydrolysates which could be used for industrial application.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.221-224
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• 2002

In vitro and in vivo activities of a biocontrol agent, Serratia plymuthica strain A2l-4, was evaluated for the control of Phytophthora blight of pepper, Strain A2l-4 inhibited mycelial growth, germination of zoosporangia and cystospores, and formation of zoospore and zoosporangia of Phytophthora capsici in vitro. In the pot experiment, incidence of Phytophthora blight of pepper in non-treated control was 100% at 14 days after inoculation, while no disease was observed in the plot treated with S. plymuthica A2l-4. In the greenhouse test, infection rate of pepper in the non-treated plots was 74.5%, while it was only 12.6％ in the plots treated with A2l-4. Results indicate that S. plymuthica A2l-4 is a potential biocontrol agent for Phytophthora blight of pepper.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.407-413
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• 1996

A novel type of extracellular phospholipase $A_1$ was isolated from Serratia sp. MK1 and purified to homogeneity by ammonium sulfate precipitation, anion exchange and gel filtration chromatography. The purified enzyme was a monomer with a molecular mass of about 43, 000 Da. This enzyme showed the highest lipolytic activity toward phosphatidylserine among the phosphoglycerides tested, and preferentially catalyzed the hydrolysis of the ester bond in phosphatidic acid to lyso-phosphatidic acid. Enzyme activity was completely inhibited by the addition of a chelating agent such as EDTA, and inhibited enzyme activity was fully recovered by the presence of $Ca^{2+}$. This implies that the enzyme requires $Ca^{2+}$ for activity. The enzyme was stable up to $70^{\circ}C$ when incubated for 1 h at pH 8.5, and the optimal pH and temperature were 8.5 and $50^{\circ}C$, respectively.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.89-92
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• 2008

The pirarucu, Arapaima gigas (body weight = 18.3 kg and total length = 102 cm) which had been reared in one of the private commercial aquaria for exhibition was found dead and submitted for diagnostic examination. A pure bacterial culture was isolated from the kidney, which was enlarged, and contained fluids. Result of the bacterial identification yielded Serratia fonticola. This paper describes the first isolation of S. fonticola from pirarucu.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.258-261
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• 1997

For the efficient production of lysophospholipid the hydrolysis of phospholipid using phospholipase $A_1$ from Serratia sp. MK1 was studied in an aqueous-solvent, a two-phase and an emulsion system. Judged on the basis of productivity and the degree of hydrolysis, the yield of lysophospholipid in a two-phase system was found to be better than that obtained in an emulsion system. Among the 13 organic solvents tested phospholipase $A_1$ showed the most efficient catalytic activity and stability in butyl acetate. When 20% phospholipid was used it was completely hydrolyzed in this two-phase system.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.408-413
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• 2007

Putrescine has a negative effect on health and is also used as an indicator of quality on meat products. We investigated the genes involved in putrescine production by Serratia liquefaciens IFI65 isolated from a spoiled Spanish dry-cured ham. We report here the genetic organization of its ornithine decarboxylase encoding region. The 5,506-bp DNA region showed the presence of three complete and two partial open reading frames. Putative functions have been assigned to several gene products by sequence comparison with proteins included in the databases. The second gene putatively coded for an ornithine decarboxylase. The functionality of this decarboxylase has been experimentally demonstrated by complementation to an E. coli defective mutant. Based on sequence comparisons of some enterobacterial ornithine decarboxylase regions, we have elaborated a hypothetical pathway for the acquisition of putrescine biosynthetic genes in some Enterobacteriaceae strains.

• BMB Reports
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• v.31 no.1
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• pp.37-43
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• 1998

The catabolic ${\alpha}$-acetolactate synthase was purified to homogeneity from Serratia marcescens ATCC 25419 using ammonium sulfate fractionation, DEAE-Sepharose, Phenyl-Sepharose, and Hydroxylapatite column chromatography. The native molecular weight of the enzyme was approximately 150 kDa and composed of two identical subunits with molecular weights of 64 kDa each. The N-terminal amino acid sequence of the enzyme was determined to be Ala-Gln-Glu-Lys-Thr-Gly-Asn-Asp-Trp-Gln-His-Gly-Ala-Asp-Leu-Val-Val-Lys-Asn-Leu. It was not inhibited by the branched chain amino acids and sulfometuron methyl herbicide. The optimum pH of the enzyme was around pH 5.5 and the pI value was 6.1. The catabolic ${\alpha}$-acetolactate synthase showed weak immunological relationships with recombinant tobacco ALS, barley ALS, and the valine-sensitive ALS isozyme from Serratia marcescens.