• Title/Summary/Keyword: ArsH

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Isolation and ars Detoxification of Arsenite-Oxidizing Bacteria from Abandoned Arsenic-Contaminated Mines

  • Chang, Jin-Soo;Yoon, In-Ho;Kim, Kyoung-Woong
    • Journal of Microbiology and Biotechnology
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    • v.17 no.5
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    • pp.812-821
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    • 2007
  • The ecosystems of certain abandoned mines contain arsenic-resistant bacteria capable of performing detoxification when an ars gene is present in the bacterial genome. The ars gene has already been isolated from Pseudomonas putida and identified as a member of the membrane transport regulatory deoxyribonucleic acid family. The arsenite-oxidizing bacterial strains isolated in the present study were found to grow in the presence of 66.7 mM sodium arsenate($V;\;Na_2HAsO_4{\cdot}7H_2O$), yet experienced inhibited growth when the sodium arsenite($III;\;NaAsO_2$) concentration was higher than 26 mM. Batch experiment results showed that Pseudomonas putida strain OS-5 completely oxidized 1 mM of As(III) to As(V) within 35 h. An arsB gene encoding a membrane transport regulatory protein was observed in arsenite-oxidizing Pseudomonas putida strain OS-5, whereas arsB, arsH, and arrA were detected in strain OS-19, arsD and arsB were isolated from strain RW-18, and arsR, arsD, and arsB were found in E. coli strain OS-80. The leader gene of arsR, -arsD, was observed in a weak acid position. Thus, for bacteria exposed to weak acidity, the ars system may cause changes to the ecosystems of As-contaminated mines. Accordingly, the present results suggest that arsR, arsD, arsAB, arsA, arsB, arsC, arsH, arrA, arrB, aoxA, aoxB, aoxC, aoxD, aroA, and aroB may be useful for arsenite-oxidizing bacteria in abandoned arsenic-contaminated mines.

Ferric Reductase Activity of the ArsH Protein from Acidithiobacillus ferrooxidans

  • Mo, Hongyu;Chen, Qian;Du, Juan;Tang, Lin;Qin, Fang;Miao, Bo;Wu, Xueling;Zeng, Jia
    • Journal of Microbiology and Biotechnology
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    • v.21 no.5
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    • pp.464-469
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    • 2011
  • The arsH gene is one of the arsenic resistance system in bacteria and eukaryotes. The ArsH protein was annotated as a NADPH-dependent flavin mononucleotide (FMN) reductase with unknown biological function. Here we report for the first time that the ArsH protein showed high ferric reductase activity. Glu104 was an essential residue for maintaining the stability of the FMN cofactor. The ArsH protein may perform an important role for cytosolic ferric iron assimilation in vivo.

Selection of optimum medium for mass production of Metarhizium anisopliae ARS 978 (Metarhizium anisopliae ARS 978의 대량 배양을 위한 배지 조건)

  • Moon, Ki-Hyuk;Yoon, Jeong-Weon;Yoon, Cheol-Sik;Kim, Seung-Wook
    • The Korean Journal of Pesticide Science
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    • v.2 no.2
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    • pp.90-96
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    • 1998
  • The purpose of this study is to investigate the liquid culture conditions for mass production of Metarhizium anisopliae var. majus ARS 978 which is a potential microbiological pesticide. The temperature and pH range for optimal cultivation were $28^{\circ}C$ and pH 7.0, respectively. For M. anisopliae ARS 978, 1.0 %(v/v) molasses, 1.0 %(w/v) distiller's dry solubles, and 0.3 %(w/v) $CaCO_{3}$ were found to be the proper nutrients, considering cell mass, enzyme activities and spore concentration.

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TREATMENT OF CLASS II DIVISION 1 MALOCCLUSION WITH L-ARS(LIGATED ANTERIOR REPOSITIONING SPLINT) (L-ARS를 이용한 Cl II div. 1 부정교합의 치험례)

  • Kim, Jong-Chul;Williamson, Eugene H.
    • The korean journal of orthodontics
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    • v.23 no.4 s.43
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    • pp.447-454
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    • 1993
  • Patient with skeletal class II relationship was treated with L-ARS. L-ARS is fixed functional appliance that could be effective in children and adolescent patient who don't wear activator. The following results were obtained ; 1) Growth of Mandible was stimulated and overjet was decreased, therefore coupling of anterior teeth was established with L-ARS which is fixed functional appliance. 2) These changes were accomplished with Mandibular skeletal growth with no effect on the Maxilla. 3) L-ARS was especially effective on patient who deny to wear the removable functional appliance.

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Classification of Pathological Voice from ARS using Neural Network (신경회로망을 이용한 ARS 장애음성의 식별에 관한 연구)

  • Jo, C.W.;Kim, K.I.;Kim, D.H.;Kwon, S.B.;Kim, K.R.;Kim, Y.J.;Jun, K.R.;Wang, S.G.
    • Speech Sciences
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    • v.8 no.2
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    • pp.61-71
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    • 2001
  • Speech material, which is collected from ARS(Automatic Response System), was analyzed and classified into disease and non-disease state. The material include 11 different kinds of diseases. Along with ARS speech, DAT(Digital Audio Tape) speech is collected in parallel to give the bench mark. To analyze speech material, analysis tools, which is developed local laboratory, are used to provide an improved and robust performance to the obtained parameters. To classify speech into disease and non-disease class, multi-layered neural network was used. Three different combinations of 3, 6, 12 parameters are tested to obtain the proper network size and to find the best performance. From the experiment, the classification rate of 92.5% was obtained.

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Arsenite Oxidation by Bacillus sp. Strain SeaH-As22w Isolated from Coastal Seawater in Yeosu Bay

  • Chang, Jin-Soo;Kim, In-S.
    • Environmental Engineering Research
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    • v.15 no.1
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    • pp.15-21
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    • 2010
  • This study was conducted to evaluated seawater bacteria and their seasonal characteristics in the arsenic contaminated coastal seawater of Yeosu Bay, the Republic of Korea. Arsenite-oxidizing bacteria play an important role in the seawater of the arsenic contaminated bay, with a variety of arsenic resistance system (ars) genotypes being present during summer. Specifically, Bacillus sp. strain SeaH-As22w (FJ607342), isolated from the bay, were found to contain the arsB, arrA and aoxR type operons, which are involved in arsenic resistance. The isolated bacteria showed relatively high tolerance to sodium arsenite (III; $NaAsO_2$) at concentrations as high as 50 mM. Additionally, batch seawater experiments showed that Bacillus sp. strain SeaH-As22w completely oxidized 1 mM of As (III) to As (V) within 10 days. Ecologically, the arsenic-oxidizing potential plays an important role in arsenic toxicity and mobility in As-contaminated coastal seawater of Yeosu Bay during all seasons because it facilitates the activity of Bacillus sp. groups.

Simulation Analysis of Active Roll Stabilizer for Automotives Based on AMESim

  • Liu, H.;Lee, J.C.;Yo, Y.C.
    • 유공압시스템학회:학술대회논문집
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    • 2010.06a
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    • pp.70-73
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    • 2010
  • In order to provide theoretical analysis for the active roll stabilizer (ARS), the simulation model based on AMESim is developed in the paper. The simplified vehicle rolling motion model is derived firstly, and then the entire ARS control system model is constructed. Furthermore, the simulation is implemented to confirm the roll control effect. The simulation results show that the derived model can be used as theoretical analysis for developing components of ARS control system.

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Comparison of Dry Matter Intake, Digestibility, and Nitrogen Balance in Spotted Deer (Cervus nippon) fed Forest by-product Silage, Arrowroot (Pueraria thunvegiana) Silage and Oak Browse (Quercus aliena) Hay (꽃사슴에 있어서 육림부산물 사일리지, 칡 사일리지 및 갈잎건초 급여에 따른 건물채식량, 소화율 및 질소출납의 비교)

  • Jeon, B.T.;Kim, Y.H.;Lee, S.M.;Kim, K.H.;Moon, S.H.
    • Journal of Animal Science and Technology
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    • v.44 no.1
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    • pp.87-94
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    • 2002
  • A comparison of intake, digestibility and nitrogen balance in spotted deer(Cervus nippon) fed forest by-product silage(FBS), arrowroot silage(ARS) and oak leaf hay(OLH) was made to examine the feeding value of forest by-product silage. Dry matter digestibility of ARS was significantly higher(p$<$0.05) than that of OLH while crude protein digestibility was significantly higher(p$<$0.05) in ARS and FBS than in OLH. The digestibility of crude fiber was highest in FBS. Dry matter intake of OLH was significantly higher(p$<$0.05) than that of ARS, and there was no significant difference with FBS. Nitrogen intake was higher in OLH and ARS than in FBS, but there was no significant difference. Fecal nitrogen was highest(p$<$0.05) in OLH and urinary nitrogen was highest(p$<$0.05) in ARS. Retained nitrogen was highest in FBS, however, there was no significant difference among treatments. In Conclusion. FBS was estimated as a useful roughage source for deer, showing high digestibility, dry matter intake and nitrogen utilization.

Leucaena leucocephala and Gliricidia sepium Supplementation in Sheep Fed With Ammonia Treated Rice Straw: Effects on Intake, Digestibility, Microbial Protein Yield and Live-Weight Changes

  • Orden, E.A.;Abdulrazak, S.A.;Cruz, E.M.;Orden, M.E.M.;Ichinohe, T.;Fujihara, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.12
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    • pp.1659-1666
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    • 2000
  • Two experiments were conducted to determine the effects of Leucaena leucocephala (leucaena) and Gliricidia sepium (gliricidia) supplementation on intake, digestion, outflow rates, microbial protein yield and live-weight changes in sheep fed with ammoniated rice straw (ARS). In experiment 1, three rumen cannulated Japanese Corriedale wether (mean body weight of 35.6 kg) in $3{\times}3$ Latin Square Design were used. Animals were fed ad libitum ARS alone, or supplemented with 200 g of either leucaena or gliricidia. In experiment 2, twenty-four growing native Philippine sheep with average body weight of $13.5{\pm}0.25kg$ were used in a completely randomized design (CRD) and offered similar diets to those of experiment 1. Supplementation increased total dry matter intake and nutrient digestibility except for fiber (p<0.05) without affecting ARS consumption. Nitrogen balance revealed that absorbed and retained N was significantly higher in leucaena and gliricidia. The significant improvement in N utilization and more digestible OM intake brought about by the inclusion of leucaena and gliricidia to ARS resulted in increased (p<0.05) microbial N yield. Efficiency of microbial N supply in supplemented group was not significantly different, but higher (p<0.05) than the 24.92 g N/kg DOMR for ARS group. Liquid outflow rate was 7.8 and 6.8 %/h, while the solid phase of rumen digesta was 4.4 and 3.8 %/h for the leucaena and gliricidia group respectively, which were significantly higher than 5.30 and 2.50 %/h in the control diet. The increase in total DMI resulted to higher (p<0.01) growth performance and efficient feed utilization. Average daily gain (ADG) was 19.3, 34.6 and 33.9 g/d for the ARS, leucaena and gliricidia respectively. It is therefore concluded that addition of leucaena and gliricidia to ARS in could increase nutrient intake and digestibility, subsequently improving N utilization and livestock performance.