• Title/Summary/Keyword: E. coli concentration

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Cotton GhKCH2, a Plant-specific Kinesin, is Low-affinitive and Nucleotide-independent as Binding to Microtubule

  • Xu, Tao;Sun, Xuewei;Jiang, Shiling;Ren, Dongtao;Liu, Guoqin
    • BMB Reports
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    • v.40 no.5
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    • pp.723-730
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    • 2007
  • Kinesin is an ATP-driven microtubule motor protein that plays important roles in control of microtubule dynamics, intracellular transport, cell division and signal transduction. The kinesin superfamily is composed of numerous members that are classified into 14 subfamilies. Animal kinesins have been well characterized. In contrast, plant kinesins have not yet to be characterized adequately. Here, a novel plant-specific kinesin gene, GhKCH2, has been cloned from cotton (Gossypium hirsutum) fibers and biochemically identified by prokaryotic expression, affinity purification, ATPase activity assay and microtubule-binding analysis. The putative motor domain of GhKCH2, $M_{396-734}$ corresponding to amino acids Q396-N734 was fused with 6$\times$His-tag, soluble-expressed in E. coli and affinity-purified in a large amount. The biochemical analysis demonstrated that the basal ATPase activity of $M_{396-734}$ is not activated by $Ca^{2+}$, but stimulated 30-fold max by microtubules. The enzymatic activation is microtubule-concentration-dependent, and the concentration of microtubules that corresponds to half-maximum activation was about 11 ${\mu}M$, much higher than that of other kinesins reported. The cosedimentation assay indicated that $M_{396-734}$ could bind to microtubules in vitro whenever the nucleotide AMP-PNP is present or absent. As a plant-specific microtubule-dependent kinesin with a lower microtubule-affinity and a nucleotide-independent microtubule-binding ability, cotton GhKCH2 might be involved in the function of microtubules during the deposition of cellulose microfibrils in fibers or the formation of cell wall.

Identification of two coliphages from Han-river and its adsorption-elution effect on soil materials (한강에서 분리한 이종 coliphage의 동정과 점토질에 대한 흡착 및 용출효과)

  • 홍순우;하영칠;안태석;이영숙
    • Korean Journal of Microbiology
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    • v.20 no.4
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    • pp.210-222
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    • 1982
  • Coliphages isolated from Han-River from September 1980 to August 1981 were classified by morphological and physiological characteristics. Effects of soil metrial on the fate of coliphage in nature were investigated. 1. The correlation coefficient between coliphage and E.coli which was host of coliphages in nature was 0.7173 (p=0.004). 2. Coliphage I isolated from Han-River of which DNA molecular weight was $27{\times}10^6$ daltons was identified as $T_1$ phage and coliphage II of which DNA molecular weight $72{\times}10^6$ daltons was classified as $T_5$ phage. 3. Soil material SW was composed of 63.65% silt and 21.92% clay. Clay was consisted of illite, kaolinite and chlorite evenly. Soil material J was composed of 68.92% silt and 11.67% clay. Clay consisted of smectite only. 4. Coliphage was absorbed to soil material J more than soil material SW, and $T_1$ coliphage was absorbed to soil material more than $T_5$ coliphage was. 5. The phage adsorption efficiency to soil material was enhanced at lower pH : the phage adsorption efficiency at pH 4 was 27 time higher than at pH 7. 6. Divalent $(Ca^{2+})\;and\;trivalention\;(Al^{3+})$ enhanced the phage adsorption efficiency to soil material from 4 to 39 and from 17 to 91 times higher than monovalent $ion(Na^+)$, respectively. 7. The concentration of organic compound was inversely related to the phage adsorption efficiency to soil. 8. Adsorption of phage onto soil material, and elution efficiency of elutants was in the order of D.D.W>tap water>river water>seawater. 9. The higher the concentration of organic compound was, the more were adsorbed phages to soil eluted. 10. Coliphages survived longer in sterile soil suspension than in nonsterile soil material suspension.

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Feasibility Study of Intermittent Slow Sand Filtration for Agricultural Reuse of Reclaimed Water (농업적 용수재이용을 위한 간헐분사 완속모래여과 하수재처리 효율 평가)

  • 윤춘경;정광욱;함종화;황하선
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.45 no.5
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    • pp.160-170
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    • 2003
  • A pilot study was performed to examine the feasibility of intermittent slow sand filtration for agricultural reuse of reclaimed water. The effluent of biofilter for 16-unit apartment was used as influent to the slow sand filtration system at 0.6 $m^3$/day loading rate using 15 seconds spray in every 10 minutes on the about 1 $m^2$ surface area and 0.5 m depth. The influent concentrations of total coliform (TC), fecal coliform (FC) and E. coli were in the range of 10.000 MPN/100 mL. and they were reduced to less than 1,000 MPN/100 mL after filtration with average of 320, 270, and 154 MPN/100 mL, respectively, showing over 95 % removal. Turbidity and SS were improved effectively and their average concentration was reduced to 0.8 NTU and 1.7 mg/L, respectively, and removal rate was about 50 %. Average BOD and COD concentrations were also reduced substantially to 2.6 and 25.8 mg/L with about 55 and 21 % removal rate, respectively. Nutrients removal was relatively low and removal rate for T-N and T-P was low however, remaining nutrients might be beneficial and less concerned in case of agricultural reuse. The concentration of biofilter effluent used in this experiment was in the range of secondary treatment effluent but slightly stronger than the one from existing wastewater treatment plants (WWTPs). Therefore, intermittent slow sand filtration might be also applicable to the effluent from WWTPs as long as its agricultural reuse is available. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, the intermittent slow sand filtration was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water. This paper is a preliminary result from pilot study and further investigations are recommended on the optimum design parameters before full scale application.

Comparison of Antibacterial Activities of Green Tea Extracts and Preservatives to the Pathogenic Bacteria (녹차추출물과 보존료의 식중독세균에 대한 항균활성 비교)

  • 박찬성;차문석
    • The Korean Journal of Food And Nutrition
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    • v.13 no.1
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    • pp.36-44
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    • 2000
  • Survival of pathogenic bacteris(S. aureus, L. monocytogenes, E. coli and S. typhimurium) in tryptic soy broth containing green tea water extract(GTW), green tea ethanol extract(GTE), potassium sorbate (PS) and sodium benzoate(SB) stored at various pH was evaluated. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts and preservatives adjusted to pH 5.5, 6.0, 6.5 and 7.0 was inoculated approximately 105 CFU/ml of pathogenic bacteria and incubated at 35$^{\circ}C$ for 24∼48 hours. Survival of bacteria was determined by viable cell counts of bacterial culture at each pH. Minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) of green tea extracts and preservatives against pathogenic bacteria were derived from survival curves of each bacteria. Antibacterial activities of green tea extracts increased with increasing pH but those of preservatives decreased with increrasing pH. S. aureus was the most sensitive strain to GTW and GTE but the most resistant to PS and SB. The MICs of green tea extracts to S. aureus were 0.52∼0.98% at pH 5.5∼6.0 and non inhibitory at pH 7.0. S. typhimurium was the most resistant to green tea extracts while the most sensitive to SB. The MICs of green tea extracts to S. typhimurium were 0.46∼1.62% at pH 5.5∼6.0 and 2% of PS was bactericidal at pH 5.5. 1.0∼2.0% of GTE were bactericidal to all strains tested except L. m9oncytogenes at pH 7.0. GTE was most efficient at inactivating pathogenic bacteria, generally followed by GTW, PS and SB.

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Solubilities and Activities of Chloramphenicol Acetyltransferase and $\beta$-Lactamase Overproduced by the T7 Expression System in Escherichia coli (대장균에서의 T7 발현체계에 의하여 과잉생산된 클로람페니콜 아세틸전이효소와 베타-락타메이즈의 수용성과 활성)

  • Kim, Han-Bok
    • Korean Journal of Microbiology
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    • v.31 no.4
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    • pp.274-278
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    • 1993
  • Overproduced proteins in many cases result in forming insoluble inclusion bodies, and their formation might be due to high concentration of protein. To investigate how proteins become insoluble, chloramphenicol acetyltransferase (CAT) and .betha.-lactamase were overproduced, and their solubilities and activities were determined. CAT was accumulated from 9 to 45% of total cellular protein in a fully soluble form without inclusion body formation. CAT specific activity was shown to be proportional to the amount of the protein produced. Moderately produced .betha.-lactamase by the phase T7 expression system at 30.deg.C comprised only mature forms in a soluble form. However, overproduced .betha.-lactamase at 37.deg.C became insoluble. Most precursor forms of .betha.-lactamase in the cytoplasm were insoluble, whereas majority of the mature forms in the periplasm space were soluble. Also, chaperone GroE proteins which assist proper protein folding and translocation did not increase .betha.-lactamase solubility significantly under the experimental condition. It seems that the formation of inclusion bodies in the cell is related to the nature of protein itself rather than just to high concentration of protein.

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Purification and Characterization of Beta-Glucosidase from Weissella cibaria 37

  • Lee, Kang Wook;Han, Nam Soo;Kim, Jeong Hwan
    • Journal of Microbiology and Biotechnology
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    • v.22 no.12
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    • pp.1705-1713
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    • 2012
  • A gene encoding ${\beta}$-glucosidase was cloned from Weissella cibaria 37, an isolate from human feces. Sequence analysis showed that the gene could encode a protein of 415 amino acids in length, and the translated amino acid sequence showed homology (34-31%) with glycosyl hydrolase family 1 ${\beta}$-glucosidases. The gene was overexpressed in E. coli BL21(DE3) using pET26b(+) and a 50 kDa protein was overproduced, which matched well with the calculated size of the enzyme, 49,950.87 Da. Recombinant ${\beta}$-glucosidase was purified by using a his-tag affinity column. The purified ${\beta}$-glucosidase had an optimum pH and a temperature of 5.5 and $45^{\circ}C$, respectively. Among the metal ions (5mM concentration), $Ca^{2+}$ slightly increased the activity (108.2%) whereas $Cu^{2+}$ (46.1%) and $Zn^{2+}$ (56.7%) reduced the activity. Among the enzyme inhibitors (1 mM concentration), SDS was the strongest inhibitor (16.9%), followed by pepstatin A (45.2%). The $K_m$ and $V_{max}$ values of purified enzyme were 4.04 mM and 0.92 ${\mu}mol/min$, respectively, when assayed using pNPG (p-nitrophenyl-${\beta}$-D-glucopyranoside) as the substrate. The enzyme liberated reducing sugars from carboxymethyl cellulose (CMC).

Effects of Bedding Thickness of Sawdust on Environment of Cowshed Floor and Productivity of Hanwoo (깔짚 두께가 한우사 바닥환경과 생산성에 미치는 영향)

  • Kim, Seung-Gi;Park, Byung-Ki;An, Jun-Sang;Park, Myung-Ho;Ra, Chang-Six;Shin, Jong-Suh
    • Journal of Animal Environmental Science
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    • v.18 no.sup
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    • pp.65-72
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    • 2012
  • This study was conducted to investigate the effects of bedding thickness of sawdust on feed intake, blood metabolites concentration and environmental condition of cowshed floor for Hanwoo. Feed intake was increased at thicker bedding groups (15 or 20cm), compared with thinner bedding group (10cm). The thicker bedding had a positive effect on concentration of serum total protein, high density lipoprotein (HDL)-cholesterol, low density lipoprotein (LDL)-cholesterol and ${\gamma}$-glutamyltransferase (GGT). Moisture content and the number of E. Coli in the bedding material were remarkably lower in 15 and 20 cm groups, compared with 10 cm group. Based on the data obtained in this study, approximately 20 cm bedding thickness or at least over 15 cm would be maintained to improve the health condition of Hanwoo and hence to enhance the productivity.

A Study on the Evaluation of Antimicrobial Effect of Orostachys Japonicus A. Berger Ethyl Acetate Fraction (와송 에틸아세테이트 분획물의 항균효능 평가에 관한 연구)

  • Im, Eun Kyung;Yang, Jae Chan
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.2
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    • pp.488-496
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    • 2021
  • In this study, a study was conducted to utilize Orostachys japonica A. Berger EtOAc fraction extract as an antibacterial activity and cosmetic ingredient. As a result of measuring the antimicrobial activity of Orostachys japonica A. Berger EtOAc, the growth of S. aureus, S. epidermidis, and P. aeruginosa was inhibited. Among them, S. aureus was an extract of 18.35 ± 1.5 mm Orostachys japonica A. Berger EtOAc fraction at a concentration of 0.5 g / mL, showing superior antibacterial activity than methyl paraben (16.83 ± 1.0 mm), and was shown as a positive control. As a result of evaluating the MIC of the Orostachys japonica A. Berger EtOAc fraction extract through MIC measurement, the remaining strains excluding Candida. A showed a MIC of 17.5 mg/mL. As a result of evaluating the cosmetic preservation effect through the challenge test applied to the cosmetic emulsion formulation, the growth inhibitory effect of S. aureus in the emulsion containing 0.3% Orostachys japonica A. Berger EtOAc fraction extract 7 days after microbial inoculation was 100%.

Effect of Feeding Browses on the Incidence of Abortion During Pregnancy in Korean Native Goats (지엽류 급여가 임신중인 흑염소에 있어서 유산 발생에 미치는 영향)

  • Choi, S.H.;Seong, H.H.;Cho, Y.M.;Kim, Y.K.;Hur, S.N.
    • Journal of Animal Science and Technology
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    • v.44 no.6
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    • pp.711-718
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    • 2002
  • In order to investigate the effect of feeding browses on the incidence of abortion in pregnant Korean native female goats, 20 pregnant does(3${\sim}$4 month) were used as experimental animal and they grouped 4 treatments with 5 heads according to experimental diets. Each group was fed pine browse, pine browse silage, fermented pine browse, or oak browse silage. Browses intake a day was 0.36kg for oak browse silage, 0.28kg for pine browse, 0.24kg for pine browse silage, and 0.14kg for fermented pine browse. Salmonella and Fungi were not found in pine browses but they were found in oak browse silage in the amount of 7.93${\times}$$10^3$ and 11.1${\times}$$10^1$ cfu/g, respectively. E. Coliwas found 11.67${\times}$$10^1$cfu/g in oak browse silage. The incidence of abortion was 60% for fermented pine browse, 40% for pine browse silage, and 20% for pine browse feeding. Abortion did not occur by feeding oak browse silage. Progesterone concentration was similar each other regardless of normal delivery or abortion at delivery day but the concentration of estradiol was higher for normal delivery, concentration of cortisol was decreased until the delivery day in normal but increased in abortion does. The results were suggested.

Effects of Keratinase on Performance, Nutrient Utilization, Intestinal Morphology, Intestinal Ecology and Inflammatory Response of Weaned Piglets Fed Diets with Different Levels of Crude Protein

  • Wang, D.;Piao, X.S.;Zeng, Z.K.;Lu, T.;Zhang, Q.;Li, P.F.;Xue, L.F.;Kim, S.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.12
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    • pp.1718-1728
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    • 2011
  • Two experiments were conducted to investigate the in vitro ability of keratinase to hydrolyze soybean glycinin and ${\beta}$-conglycinin and to evaluate the in vivo effects of keratinase when included in corn-soybean diets with different levels of crude protein and fed to nursery pigs. In experiment 1, a saturated keratinase solution (1 ml) was added to two blank controls of either glycinin or ${\beta}$-conglycinin resulting in the hydrolysis of 94.74% glycinin and 88.89% ${\beta}$-conglycinin. In experiment 2, 190 pigs (8.3${\pm}$0.63 kg BW) were allotted to one of four treatments in a 2${\times}$2 factorial arrangement on the basis of body weight, and sex was balanced among the pens. The effects of crude protein (19 vs. 22%) and keratinase (0 vs. 0.05%) were studied. Each treatment was applied to six pens with seven (two pens) or eight pigs per pen. Pigs were fed the experimental diets for 21 d. Weight gain and feed conversion ratio were improved (p<0.05) with keratinase supplementation while feed intake was reduced (p<0.05). Keratinase supplementation increased (p<0.05) the apparent total tract digestibility of dry matter, energy, crude protein and phosphorus. Keratinase supplementation also increased n-butyric acid in the cecum and colon, lactobacilli and total anaerobe counts in the colon as well as the ratio of villus height to crypt depth in the ileum. Additionally, fecal score, ammonia nitrogen and branch chain volatile fatty acids in the colon, E. coli and total aerobe counts in the colon, crypt depth in the jejunum and ileum as well as serum interleukin-1 and interleukin-6 concentrations were also decreased (p<0.05) by keratinase supplementation. A reduction in dietary crude protein decreased (p<0.05) colon ammonia nitrogen concentration and cecal propionic acid and branch chain volatile fatty acid concentrations. In addition, cecal E. coli counts, colon total anaerobe counts, ileal crypt depth, and serum interleukin-1 and interleukin-6 concentrations were also decreased (p<0.05) with the reduction of dietary crude protein. With the exception of fecal scores, there were no significant interactions between crude protein and keratinase. This study provides evidence that dietary keratinase supplementation improved nursery pig performance by improving intestinal morphology and ecology, thus improving nutrient digestibility and alleviating the inflammatory response.