• Research in Plant Disease
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• v.9 no.4
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• pp.229-236
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• 2003

The 1080 epiphytic bacteria obtained from 370 samples of pome and stone fruits including apple, pear, peach, grape, apricot and Chinese quince were screened for antagonistic activity against postharvest pathogens, Penicillium expansum, Alternaria alternata and Botrytis cinerea. Among tested antagonistic bacteria, eight bacterial isolates inhibited mycelial growth of the postharvest pathogens and were identified as Bacillus amyloliquefaciens (three strains), B. megaterium, B. subtilis var. gladioli, B. licheniformis, B. pumilus and Serratia marcescens based on biochemical characteristics and utility of carbon and nitrogen compounds (Biolog system). Eight carbohydrates were evaluated for their effect on mycelial growth and germination of the postharvest pathogen, P. expansum to select nutrients for enhancing bio-control efficacy. The growth of four selected antagonists, B. amyloliquefaciens P43-2, B. amyloliquefaciens A71-2, B. licheniformis P94-1, and S. marcescens P76-9 were also tested. As a result, 1% glucose (w/v) strongly stimulated growth of the antagonists, suppressed mycelial growth of the postharvest pathogen, and had a little comparatively stimulatory effect on germination of the the postharvest pathogen. It was confirmed that the addition of 1% glucose (w/v) greatly enhanced biocontrol effect of B. amyloliquefaciens P43-2, B. licheniformis P94-1, and S. marcescens P76-9. Application of B. amyloliquefaciens P43-2, B. licheniformis P94-1, and S. marcescens P76-9 with the addition of 1% glucose (w/v) increased the control efficacy up to 48%, 46%, 14% compared with those of the antagonists without glucose, respectively. When the antagonists were applied to control postharvest disease caused by P. expansum in apple wounds, the population of B. amyloliquefaciens P43-2 and B. licheniformis P94-1 increased until 4 days after inoculation (DAI) of the antagonists and then decreased from 10 DAI. Meanwhile the population of S. marcescens P76-9 decreased at early stage (4 DAI), but increased from 7 DAI, and finally maintained constantly until 10 DAI in apple wounds.

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.39-43
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• 1999

Serratia marcescens, an enterobacterium of gram-negative bacteria, is characterized by resistance of the admium. Cadmium sensitive PM strain did not grow in the medium at cadmium concentration of 50 ppm. PA strain was induced to accommodate to cadmium by cultivating the mother strain (PC strain) in the medium with 50 ppm cadmium. As compared with PC and PM strains, PA strain revealed the excellent growth in cadmium media and accumulated four to five times higher cadmium concentration in cell than other strains. PA strain accumulated 23% of cadmium in cells when cultured in medium treated with 100 ppm cadmium and this cadmium was more accumulated in cytosol fractions than membrane fractions. Analysis by TEM indicated that cadmium was concentrated as a form of granule in cytosol. In protein patterns of cell after the treatment of cadmium, two inducible proteins (28 KDa and 64 KDa) and one reducible protein (45 KDa) were detected by SDS-PAGE. By Atomic Absorption Spectrophotometer, the amounts of cadmium attached to inducible proteins of 28 KDa and 64 KDa were 318.28 ㎍ and 325.37 ㎍ per gram of protein, respectively. It is assumed that these inducible proteins play an important role in the mechanism of cadmium accumulation in cells. A plasmid of 23Kbp was found in S. marcescens. The ability of resistance to cadmium in plasmid was confirmed by curing experiments.

• Archives of Pharmacal Research
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• v.10 no.4
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• pp.228-231
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• 1987

Studies on the adsorption of four kinds of bacteria, Staphylococcus aureus, Sarcina lutea, Escherichia coli and Serratia marcescens by activated Korean Kaoline have been carried out to innovate utilization as adsosrbent preparations. In connection with particle size and size fraction, the adsorption was examined by colony counting and spectroscopy. Korean kaolin was purified from Hadong white species of preminum grade and three size fractions were derived from passage through BS # 100, #200 and # 325 mesh sieves, respectively. These were activated at $105^{\circ}$or $280^{\circ}$ for three hours and at $550^{\circ}C$ for one hours. The results indicated that the adsorbing power of Korean kaolin was superior for S. aureus and S. lutea, but E. coli and S. marcescens were not adsorbed by clays. The smaller the particle size, the greater was adsorbing power for Gram-positive bacteria. Threre appears to be justification for its investigations as an ingredient in intestinal adsorbent preparations.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.430-437
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• 2011

The effects of the agitation and aeration rates on the production of serratiopeptidase (SRP) in a 5-L fermentor (working volume 2-l) were systematically investigated using Serratia marcescens NRRL B-23112. The dissolved oxygen concentration, pH, biomass, SRP yield, and maltose utilization were all continuously measured during the course of the fermentation runs. The efficiencies of the aeration and agitation were evaluated based on the volumetric mass transfer coefficient ($K_La$). The maximum SRP production of 11,580 EU/ml with a specific SRP productivity of 78.8 EU/g/h was obtained with an agitation of 400 rpm and aeration of 0.075 vvm, which was 58% higher than the shake-flask level. The $K_La$ for the fermentation system supporting the maximum production (400 rpm, 0.075 vvm) was 11.3 $h^{-1}$. Under these fermentor optimized conditions, kinetic modeling was performed to understand the detailed course of the fermentation process. The resulting logistic and Luedeking-Piret models provided an effective description of the SRP fermentation, where the correlation coefficients for cell growth, SRP formation, and substrate consumption were 0.99, 0.94, and 0.84, respectively, revealing a good agreement between the model-predicted and experimental results. The kinetic analysis of the batch fermentation process for the production of SRP demonstrated the SRP production to be mixed growth associated.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.694-699
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• 2000

Serratia marcescens IRBG500 and Herbaspirillum seropedicae Z67 grow endophytically in rice. The ability of these bacteria to colonize rice grown under increased nutrient availability was assessed in variety IR72 using strains marked with transposon-based gusA. The endophytic colonization was monitored via bacterial enumeration and histochemical visualization of GUS expression of bacteria in plant tissues. Rhizoplane and endophytic colonization by both bacteria was significantly inhibited in the rice plants grown in the presence of 10 mM $NH_4Cl$. In contrast, the addition of 10 mM $KNO_3$ showed no adverse effect on colonization. Increasing the concentration of $Ca^{2+}$ to 5 mM significantly reduced endophytic colonization by both bacterial strains, whereas the addition of 0.5 mM $Fe^{2+}$ substantially lowered the colonization of roots by S. marcescens IRBG500 but showed no effect on colonization by H. seropedicae Z67. Taken together, these finding suggest that, like in legume-rhizobial symbiosis as well as plant-pathogen interactions, nutrient status, particularly $NH_4^+$ and $Ca^{2+}$ concentrations in the surrounding medium, plays an important role in the regulation of endophytic infection and colonization processes in rice.

• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.870-875
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• 2001

A DNA fragment, pCKB13, containing two genes encoding Coenzyme a transferase, was isolated from a genomic DNA library of S. marcescens KCTC 2172. The complete nucleotide sequence of the 2,081-bp BamHI fragment on pCKB13 was determined. Sequencing of the fragment led to the identification of two open reading frames showing high homology with two Coenzyme A (CoA) transferases, Acetoacetyl-CoA transferase (Acot) and Succinyl-CoA transferase (Scot), enzymes catalyzing the reversible transfer of CoA from one carboxylic acid to another. The enzyme activity of Coenzyme A transferase increased after introducing the multicopy of the cloned gene in E. coli. The recombinant protein, overexpressed by multicopy and induction with IPTG, was a polypeptide of 42 kDa, as confirmed by SDS-PAGE. The protein was purified to homogeneity through three sequential chromatographic procedures including ion-exchanged DEAE-sepharose, CM-sepharose, and Mono Q.

• Korean Journal of Environmental Agriculture
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• v.20 no.5
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• pp.335-339
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• 2001

Two successive in vitro experiments were carried out to examine the effect of MPS bacterial inoculation on growth, and nitrogen and phosphorus accumulation of maize plants under greenhouse condition in the same soil. There were four treatments, uninoculated control and three phosphate solubilizing bacterial inoculations, viz., Pseudomonas striata, Burkholderia cepacia and Serratia marcescens. The inoculated plants showed the higher plant height, total dry mass, nitrogen and phosphorus accumulation when compared to uninoculated control plants in both experiments. In the combined data analysis from two experiments, the plants inoculated with P. striata and B. cepacia showed significantly higher plant height, total dry mass and P accumulation when compared to S. marcescens inoculated plant and uninoculated control plants. The P. striata and B. cepacia inoculation enhanced total dry matter accumulation by 14% and phosphorus accumulation by 25% over the uninoculated control plants. The nitrogen and phosphorus concentration of maize plants were also increased due to MPS bacterial inoculation, however, the effect was not significant.

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.596-606
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• 2019

N-acyl-homoserine lactone quorum sensing (AHL-QS) has been shown to regulate many physiological behaviors in Serratia marcescens MG1. In the current study, the effects of AHL-QS on the biosynthesis of acid and neutral products by S. marcescens MG1 and its isogenic ${\Delta}swrI$ with or without supplementing exogenous N-hexanoyl-L-homoserine lactone ($C_6-HSL$) were systematically investigated. The results showed that swrI disruption resulted in rapid pH drops from 7.0 to 4.8, which could be restored to wild type by supplementing $C_6-HSL$. Furthermore, fermentation product analysis indicated that ${\Delta}swrI$ could lead to obvious accumulation for acidogenesis products such as lactic acid and succinic acid, especially excess acetic acid (2.27 g/l) produced at the early stage of fermentation, whereas solventogenesis products by ${\Delta}swrI$ appeared to noticeably decrease by an approximate 30% for acetoin during 32-48 h and by an approximate 20% for 2,3-butanediol during 24-40 h, when compared to those by wild type. Interestingly, the excess acetic acid produced could be removed in an AHL-QS-independent manner. Subsequently, quantitative real-time PCR was used to determine the mRNA expression levels of genes responsible for acidogenesis and solventogenesis and showed consistent results with those of product synthesis. Finally, by close examination of promoter regions of the analyzed genes, four putative luxI box-like motifs were found upstream of genes encoding acetyl-CoA synthase, lactate dehydrogenase, ${\alpha}$-acetolactate decarboxylase, and Lys-like regulator. The information from this study provides a novel insight into the roles played by AHL-QS in switching from acidogenesis to solventogenesis in S. marcescens MG1.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1433-1436
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• 2008

Flagellate bacteria such as Escherichia coli or Serratia marcescens possess a remarkable motility system based on a reversible rotary motor. We have employed S. marcescens as microactuators in low Reynolds number fluidic environments to move a larger engineering element around. Microstructures fabricated using conventional microfabrication techniques are blotted on the swarm plate, which leaves a bacterial monolayer on the surface of the microstructure. We have investigated microstructures powered by bacteria to determine how cell orientation on the microstructure surface relates to the swarming patterns as well as how the orientation is affected by the blotting process. This study will help to refine directional control of bacterial transporters by exploiting bacterial sensory mechanisms.

• Journal of Life Science
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• v.20 no.1
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• pp.77-81
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• 2010

We separated the bacteria showing protease activity from Reticulitermes speratus which is known as the only termite species in Korea. Then, we collected the best activated strain and studied the optimal culture condition for producing the enzyme. According to the results of observing morphological and physiological characteristics, and the type of 16S rRNA of the strain, it was identified as Serratia marcescens and named S. marcescens strain TM-3215. This strain showed the best activity under conditions of 0.8% (w/v) starch, 0.4% (w/v) peptone, 0.08% (w/v) $MgSO_4{\cdot}7H_2O$, $30^{\circ}C$ and pH 8.0. After being cultivated under optimal conditions for 9 hr, the strain produced 19.8 U/ml of enzyme, an amount 1.8 times greater than the control.