• Asian-Australasian Journal of Animal Sciences
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• 제25권3호
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• pp.382-392
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• 2012

This study evaluated the effects of dietary anticoccidial drugs plus antibiotic growth promoters (AGPs) on parameters of immunity in commercial broiler chickens. Day-old chicks were raised on used litter from a farm with endemic gangrenous dermatitis to simulate natural pathogen exposure and provided with diets containing decoquinate (DECX) or monensin (COBN) as anticoccidials plus bacitracin methylene disalicylate and roxarsone as AGPs. As a negative control, the chickens were fed with a non-supplemented diet. Immune parameters examined were concanavalin A (ConA)-stimulated spleen cell proliferation, intestine intraepithelial lymphocyte (IEL) and spleen cell subpopulations, and cytokine/chemokine mRNA levels in IELs and spleen cells. ConA-induced proliferation was decreased at 14 d post-hatch in DECX-treated chickens, and increased at 25 and 43 d in COBN-treated animals, compared with untreated controls. In DECX-treated birds, increased percentages of $MHC2^+$ and $CD4^+$ IELS were detected at 14 d, but decreased percentages of these cells were seen at 43 d, compared with untreated controls, while increased $TCR2^+$ IELs were evident at the latter time. Dietary COBN was associated with decreased fractions of $MHC2^+$ and $CD4^+$ IELs and reduced percentages of $MHC2^+$, $BU1^+$, and $TCR1^+$ spleen cells compared with controls. The levels of transcripts for interleukin-4 (IL-4), IL-6, IL-17F, IL-13, CXCLi2, interferon-${\gamma}$ (IFN-${\gamma}$), and transforming growth factor${\beta}$4 were elevated in IELs, and those for IL-13, IL-17D, CXCLi2, and IFN-${\gamma}$ were increased in spleen cells, of DECX- and/or COBN-treated chickens compared with untreated controls. By contrast, IL-2 and IL-12 mRNAs in IELs, and IL-4, IL-12, and IL-17F transcripts in spleen cells, were decreased in DECX- and/or COBN-treated chickens compared with controls. These results suggest that DECX or COBN, in combination with bacitracin and roxarsone, modulate the development of the chicken post-hatch immune system.

• BMB Reports
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• 제35권3호
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• pp.330-336
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• 2002

The lgtB genes that encode $\beta$-1,4-galactosyltransferases from Neisseria meningitidis ATCC 13102 and gonorrhoeae ATCC 31151 were isolated by a polymerase chain reaction using the pfu DNA polymerase. They were expressed under the control of lac and T7 promoters in Escherichia coli M15 and BL21 (DE3). Although the genes were efficiently expressed in E. coli M15 at $37^{\circ}C$ (33 kDa), most of the $\beta$-1,4-galactosyltransferases that were produced were insoluble and proteolysed into enzymatically inactive polypeptides that lacked C-terminal residues (29.5 kDa and 28 kDa) during the purification steps. When the temperature of the cell growth was lowered to $25^{\circ}C$, however, the solubility of the $\beta$-1,4-galactosyltransferases increased substantially. A stable N-terminal his-tagged recombinant enzyme preparation could be achieved with E. coli BL21 (DE3) that expressed lgtB. Therefore, the cloned $\beta$-1,4-galactosyltransferases were expressed under the control of the T7 promoter in E. coli BL21 (DE3), mostly to the soluble form at $25^{\circ}C$. The proteins were easily purified to homogeneity by column chromatography using Ni-NTA resin, and were found to be active. The galactosyltransferases exhibited pH optimum at 6.5-7.0, and had an essential requirement for the $Mn^{+2}$ ions for its action. The $Mg^{+2}$ and $Ca{+2}$ ions showed about half of the galactosyltransferase activities with the $Mn^{+2}$ ion. In the presence of the $Fe^{+2}$ ion, partial activation was observed with the $\beta$-1,4-galactosyltransferase from N. meningitidis(64% of the enzyme activity with the $Mn^{+2}$$Ni^{+2}$, $Zn^{+2}$, and $Cu^{+2}$ ions could not activate the $\beta$-1,4-galactosyltransferase activity. The inhibited enzyme activity with the $Ni^{+2}$ ion was partially recovered with the $Mn^{+2}$$Fe^{+2}$, $Zn^{+2}$, and $Cu^{+2}$ ions, the $Mn^{+2}$$\beta$-1,4-galactosyltransferase activity was 1.5-fold stimulated with the non-ionic detergent Triton X-100 (0.1-5%).

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.267-274
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• 2009

Two experiments were conducted to investigate the feeding value of wood vinegar in weanling pigs. In Experiment 1, weanling pigs (n = 224; Landrace ${\times}$Yorkshire ${\times}$Duroc, 21${\pm}$3 d-old, initial BW 6.12${\pm}$0.10 kg) were assigned to four dietary treatments. Different levels of wood vinegar were added to the diets as dietary treatments (0, 0.1, 0.2 and 0.3%). Each treatment comprised 4 replicates with 14 piglets in each. Experimental feeding was conducted for 28 d in two phases (phase I, d 0 to 14 and phase II, d 15 to 28). Feeding of wood vinegar linearly (p<0.05) improved the phase I, phase II and overall ADG and increased (linear, p<0.05) the overall and phase II ADFI. Linear improvements in the apparent fecal digestibility of dry matter (p = 0.013), gross energy (p = 0.019) and crude protein (p = 0.033) were observed as the level of wood vinegar was increased in the diet of pigs. Experiment 2 was conducted to compare dietary wood vinegar with commonly used growth promoters, organic acid (mixture of 21% phosphoric acid, 3.25% propionic acid, 2.8% formic acid, 10% calcium formate and 5% calcium propionate) and antibiotic (aparamycin). A total of 288 weanling piglets (Landrace ${\times}$Yorkshire ${\times}$Duroc, 22${\pm}$2 d-old, initial BW 6.62${\pm}$0.31 kg) were assigned to four treatments with four replicates (18 piglets/pen) for 28 days and fed in 2 phases: phase I, d 0 to 14 and phase II, d 15 to 28. The dietary treatments were control (corn-soybean meal basal diet without antibiotics) and diets containing 0.2% antibiotic, 0.2% organic acid and 0.2% wood vinegar. Pigs fed antibiotic showed higher (p<0.001) ADG and better feed efficiency followed by pigs fed wood vinegar and organic acid diets while those fed the control diet had lowest ADG and poorest feed efficiency. The overall and phase I ADFI was highest (p<0.001) in pigs fed wood vinegar and lowest in pigs fed the control diet. Apparent fecal digestibility of dry matter, gross energy and crude protein was significantly higher (p<0.05) in pigs fed the antibiotic diet when compared with pigs fed the control but comparable among pigs fed antibiotic, organic acid and wood vinegar diets. Higher populations of Lactobacillus (p = 0.004) were noted in the ileum of pigs fed the wood vinegar diet, while the population of coliforms in the ileum and cecum was higher (p<0.001) in pigs fed the control diet when compared with pigs fed antibiotic, organic acid or wood vinegar diets. These results indicated that wood vinegar could improve the performance of weanling pigs by improving the nutrient digestibility and reducing harmful intestinal coliforms; moreover performance of pigs fed wood vinegar was superior to those fed organic acid.

• Interdisciplinary Bio Central
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• 제3권3호
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• pp.10.1-10.8
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• 2011

Introduction: Hash functions are computer algorithms that protect information and secure transactions. In response to the NIST's "International Call for Hash Function", we developed a biological hash function using the computing capabilities of bacteria. We designed a DNA-based XOR logic gate that allows bacterial colonies arranged in a series on an agar plate to perform hash function calculations. Results and Discussion: In order to provide each colony with adequate time to process inputs and perform XOR logic, we designed and successfully demonstrated a system for time-delayed bacterial growth. Our system is based on the diffusion of ${\ss}$-lactamase, resulting in destruction of ampicillin. Our DNA-based XOR logic gate design is based on the op-position of two promoters. Our results showed that $P_{lux}$ and $P_{OmpC}$ functioned as expected individually, but $P_{lux}$ did not behave as expected in the XOR construct. Our data showed that, contrary to literature reports, the $P_{lux}$ promoter is bidirectional. In the absence of the 3OC6 inducer, the LuxR activator can bind to the $P_{lux}$ promoter and induce backwards transcription. Conclusion and Prospects: Our system of time delayed bacterial growth allows for the successive processing of a bacterial hash function, and is expected to have utility in other synthetic biology applications. While testing our DNA-based XOR logic gate, we uncovered a novel function of $P_{lux}$. In the absence of autoinducer 3OC6, LuxR binds to $P_{lux}$ and activates backwards transcription. This result advances basic research and has important implications for the widespread use of the $P_{lux}$ promoter.

• Journal of Animal Science and Technology
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• 제59권8호
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• pp.18.1-18.8
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• 2017

Background: In 2006, the European Union (EU) has decided to forbid use of antibiotics as growth promoters. Although many researches had been conducted about fiber source as alternatives of antibiotics, there are still lack of reports in the literature about the optimum level of sugar beet pulp supplementation, affecting growth performance and nutrient digestibility in weaning pigs. Therefore, different level of sugar beet pulp was added to diets to determine the effects of sugar beet pulp supplementation on growth performance, nutrient digestibility, fecal microflora, blood profile and incidence of diarrhea in weaning pigs. Methods: A total of 200 weaning pigs [$(Yorkshire{\times}Landrace){\times}Duroc$], averaging $9.01{\pm}1.389kg$ of initial body weight were, allotted to 5 treatments in a randomized complete block (RCB) design. Each treatment was composed of 4 replicates with 10 pigs per pen. The treatments were control treatment: Corn-SBM basal diet + ZnO (phase 1: 0.05%; phase 2; 0.03%) and four different levels of sugar beet pulp were supplemented in Corn-SBM basal diet (3, 6, 9 or 12%). Two phase feeding programs (phase 1: 1-2 weeks; phase 2: 3-5 weeks) were used for 5 week of growth trial. Results: In feeding trial, there were no significant differences in growth performance and incidence of diarrhea among treatments. The E.coli counts were not significantly different among dietary treatments but linear response was observed in Lactobacillus counts as sugar beet pulp supplementation increased (P < 0.05). In addition, IGF-1, IgA and IgG were not affected by dietary treatments. However, the BUN concentration was decreased when pigs were fed the treatments of diets with SBP compared to that of control treatment (P < 0.05). In nutrient digestibility, crude fiber and NDF digestibilities were improved as the sugar beet pulp increased (P < 0.05). However, digestibilities of crude ash, crude fat, crude fiber and nitrogen retention were not affected by dietary sugar beet pulp levels. Conclusion: This experiment demonstrated that sugar beet pulp can be supplemented in weaning pigs' diet instead of ZnO to prevent postweaning diarrhea without any detrimental effect on growth performance.

• 한국미생물·생명공학회지
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• 제26권1호
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• pp.68-75
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• 1998

A. niger의 GOD(Glucose Oxidase) 대량생산과 효율적인 분비를 protein의 대량생산에 많이 사용되는 strain인 S. cerevisiae에서 시도하였다. S. cerevisiae의 ADH1과 GAL 10 promotor, 그리고 ${alpha}$-MF signal sequence와 A. oryzae의 ${alpha}$-amylase signal sequence 및 S. cerevisiae의 GAL7과 A. niger의 GOD terminator를 이용하여 4개의 expression vector를 합성한 후 S. cerevisiae 2805에 auxotroph 방법으로 형질변환시켰다. 변이체들을 배양하여 세포내와 세포외의 GOD활성도를 분석한 결과 GAL 10 promotor가 삽입된 pGAL변이체들이 ADH1 promotor가 삽입된 pADH 변이체들 보다 GOD 생산성이 높았다. GAL 10 promotor와 A. oryzae의 ${alpha}$-amylase signal sequence가 삽입된 pGALGO2에서 115시간 배양시 GOD의 생산이 가장 높았다($GOD_{total}$: 10.3 unit/mL, $GOD_{ex}$: 8.7 unit/mL). 이 수치는 같은 promotor인 GAL 10 promotor와 ${alpha}$-MF signal sequence가 삽입된 pGALGO1보다 3배정도 높다. 이 결과는 ADH 1 promotor를 사용하였을 경우에도 일치하였다. 또한 A. oryzae의 ${alpha}$-amylase signal sequence가 S. cerevisiae의 ${alpha}$-MF signal sequence보다 GOD를 더 효과적으로 분비시켰다. 상기 결과로 미루어 보면 signal sequence가 단백질의 분비 외에도 단백질 합성에도 많은 영향을 주는 것으로 추측된다. pGALGO1과 pGALGO2의 GOD분비효율은 각각 89%, 84%이었다. S. cerevisiae에서는 일반적으로 과당화가 일어나기 때문에 S. cerevisiae에서 합성된 재조합 GOD의 분자량은 250 kDa으로 A. niger의 GOD(170 kDa)보다 더 컸다.

• 미생물학회지
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• 제51권1호
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• pp.81-85
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• 2015

성장촉진제로 항생제 사용이 금지가 된 이후, 가축들의 사망률이 증가되어 항생제 대체제를 개발해야 하는 것이 시급하다. 그러한 대체제 개발에 새로운 접근 중 하나는 숙주의 신체적 기능에 영향을 준다고 알려진 장내미생물생태를 조절하는 것이다. 하지만 가축의 장내미생물에 대한 이해가 인간과 비교하여 볼 때 많이 부족한 실정이다. 본 연구에서는 돼지장내미생물생태가 지역적 차이가 있음에 대한 기본적인 정보를 제공한다. 돼지 분변샘플은 제주(n=40), 광주(n=28), 해남(n=30) 농가로부터 채취하였으며, MiSeq을 이용하여 16S rRNA V4 지역을 시퀀싱하였다. 또한 Mothur 파이프라인을 이용하여 MiSeq으로부터 얻은 데이터를 처리하였다. 총 5,642,125 reads를 얻었으며, 에러시퀀스들을 제거한 후 최종적으로 3,868,143 reads가 남았다. Phylum 수준의 taxonomic composition 분석에서는 제주 돼지들이 Firmicutes를 가장 많이 포함하고 있었으며, Operational Taxonomic Units 분포분석에서 또한 지역적 차이에 따라 돼지장내미생물생태가 다르다는 것을 확인하였다. Non-metric multidimensional scaling과 Phyla의 풍부함 사이의 상관관계분석에서는 Actinobacter, Verrucomicrobia, Firmicutes, Fibrobacteres이 세 개의 지역에 있는 돼지들의 장내미생물생태 차이를 나타나게 하는 장내 미생물 요소라는 것을 확인하였다. 그러한 가축의 장내미생물생태는 농장에서 사용하는 사료와 사양관리에 의해 많은 영향을 미치는 것으로 생각된다. 본 연구결과는 돼지장내미생물생태가 지역적으로 많은 차이가 있다는 것을 나타내며, 추후에 가축의 장내미생물생태에 관한 연구는 지역적 차이가 있다는 것을 고려하여 설계해야 될 것이다.

• 미생물학회지
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• 제52권3호
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• pp.249-253
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• 2016

먹물버섯의 하나인 Coprinellus congregatus는 생활사 동안 여러 종의 laccase 효소를 생성한다. 균사 끝 효소와 버섯시원체 효소 및 sclerotium (균핵) 효소들은 모두 이 균의 분화와 관련되었다. 이핵체 균사를 산성 액체배지(pH 4.0-4.5)에 접종하면 새로운 laccase가 합성되어 분비된다. 이 laccase 유전자의 프로모터의 어느 부분이 산 충격의 신호에 관련된 단백질이 결합하는가 분석하기 위하여 녹색형광단백질(green fluorescent protein, GFP) 유전자를 laccase 프로모터 2.0 kb 다음에 연결하고, 이를 형질전환 벡터인 pBARGEM7-1에 삽입함으로써 발현벡터를 구축하였다. 이 promoter-GFP 조합의 5'-region부터 차례로 제거한 짧은 길이의 이 발현벡터를 먹물버섯 교배형 a1균과 a2균에 형질전환 방법으로 도입시키고 phosphinothricin 저항성으로 형질전환체들을 선발하였다. 선발된 형질전환체 a1 (a1TF)과 a2 (a2TF)를 서로 교배하여 동형접합(homozygotic) 이핵체 형질전환체를 만들었다. 이들을 산성 액체배지에서 36시간 배양하고 균체를 모아 confocal microscope를 사용하여 형광을 분석하였다. Laccase 유전자의 전체 프로모터(2.0 kb)를 가진 발현벡터(F0-GFP)를 도입한 동형접합 형질전환체에서는 형광을 보였으나, 그 보다 짧은 길이(1.29 kb 이하)의 프로모터를 가진 형질전환체에서는 형광이 나타나지 않았다. 이 결과에 근거하여 먹물버섯의 산 충격에 대한 신호를 받는 부위가 laccase 유전자 프로모터의 -2.0 kb ~ -1.29 kb 사이에 있을 것으로 추정한다.

• 공업화학
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• 제10권2호
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• pp.252-258
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• 1999

알콕시실란 중의 하나인 tetramethyl orthosilicate (TMOS)를 금속 규소와 메탄올을 출발물질로 구리계 촉매상에서 기상 반응시키는 직접합성법으로 제조할 때, 규소와 구리촉매 및 금속 염화물 조촉매로 이루어진 접촉물질의 제조 방법 및 온도가 생성물의 수율 및 선택도에 미치는 영향을 검토하였다. 이때 구리 촉매와 함께 Zn, Sn, Cd계 화합물을 조촉매로 사용하여 그 효과를 비교하였다. 구리 공급원으로 제일염화구리를 사용하고 염화아연을 조촉매로 사용한 2원 촉매계가 가장 적합하였으며, 구리/규소 = 7 wt %, 아연/구리 = 7 wt % 조성에서 함침법을 사용하여 규소와 혼합한 후 $380^{\circ}C$에서 활성화시킨 접촉물질을 제조하여 TMOS 합성에 사용하였을 때, 반응온도 $220^{\circ}C$에서 평균선택도 87.2% 규소소모율 69.2%를 나타냈다.

• Journal of Animal Science and Technology
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• 제51권4호
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• pp.315-320
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• 2009

본 시험은 육계 사료 내 사과박 발효물, 계피 및 계피 첨가 사과박 발효물을 첨가 급여시에 육계 생산성, 혈액 성상 및 계육 내 지방산화도에 대해 미치는 영향을 조사하고자 실시하였다. 육계 Cobb 종 수컷 총 600수를 5처리 4반복 반복당 30수씩 공시하여 5주간 실험을 실시하였다. 실험 전 기간 동안 증체율 및 사료섭취량은 사과박 발효물을 급여한 처리구에서 다른 처리구에 비하여 최대 30g 이상의 유의적인 개선효과를 나타내었으며(p<0.05), 계피 및 계피 첨가 사과발효물 처리구에서는 무항생제와 비교하였을 때 유의적인 차이는 인정되지 않았다. 각 처리구간 혈액 생화학 및 혈구 분석에서는 전체 처리구 간 유의적인 차이는 없었지만 Glucose는 계피를 첨가한 처리구에서 감소효과가 나타났으며 향후 이에 대한 좀더 깊은 연구가 필요할 것으로 사료된다. 지방산화도는 각 처리구간 사이에 유의적인 차이가 나타나지 않았다. 결과적으로, 육계 사료 내 사과발효물의 첨가 급여는 육계에서 생산성을 개선시키는 효과가 있는 것으로 사료되며 현재까지 이에 대한 연구가 매우 부족하다는 것을 감안할 때 향후 이에 대한 좀더 깊은 연구가 필요할 것으로 사료된다.