• 미생물학회지
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• 제47권3호
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• pp.209-217
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• 2011

결론적으로 본 연구에서는 16S rRNA 유전자 기반의 454 pyrosequencing을 통해 혐기성 소화조에 존재하는 다양한 아케아를 규명할 수 있었으며, 지금까지 그 중요성이 잘 알려지지 않은 Methanococcales 목에 속하는 아케아가 소화조에 공통적으로 존재함을 확인할 수 있었다. 또한, 소화조의 운전조건은 아케아의 다양성과 군집구조를 결정하는데 영향을 미치는 중요한 인자라는 것을 알 수 있었다. 실규모 6개 혐기성 소화조를 대상으로 11개 소화 슬러지 시료를 채취해, 16S rRNA 유전자 기반의 454 pyrosequencing을 이용하여 아케아 군집구조를 조사하였다. 아케아 16S rRNA 유전자 염기서열로부터 측정된 observed operational taxanomic units (OTUs)는 13-55 OTUs이었으며(3% cutoff), 이는 Chao1 richness estimate로 계산된 값의 29-89%에 해당하였다. 소화조에는 메탄생성에 직접적으로 관련이 있다고 알려진 Methanomicrobiales, Methanobacteriales, Methanococcales, Methanosarcinales, Methanocellales 목에 속하는 아케아 뿐만 아니라, Thermoproteales, Thermoplasmatales, Desulfurococcales목에 속하는 아케아도 함께 발견되었다. 이 중 수소를 기질로 해서 메탄을 생성한다고 알려진 Methanoacoccales가 전체 염기서열의 51.8-99.7%를 차지해 가장 많이 발견된 분류군으로 나타났다. Heat map 분석결과 각 시료들의 아케아 군집구조는 1개 시료를 제외한 나머지 10개 시료가 매우 비슷한 군집구조를 가지고 있었다(Pearson 상관지수=0.99). 또한, 아케아 군집구조와 환경변수들의 상관성을 분석한 canonical correspondence analysis를 통해 혐기성 소화조의 아케아 군집구조에 영향을 미치는 중요 환경변수는 소화조의 온도와 총고형물 제거율임을 확인하였다. 모든 결과들을 종합해 볼 때 소화조의 운전조건은 아케아의 다양성과 군집구조를 결정하는데 영향을 미치는 중요한 인자라고 사료된다.

• 한국균학회지
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• 제47권4호
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• pp.359-371
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• 2019

큰느타리버섯에서 철 저장과 관련된 페리틴 단백질의 발현 및 분비를 최적화하기 위해, T-Fer 벡터에 EcoRI 및 HindIII처리를 해 페리틴 유전자를 얻은 후, BamHI으로 처리된 선형의 pPEVPR1b 분비 벡터에 클로닝하여pPEVPR1b-Fer 재조합 벡터를 구축한 다음 Agrobacterium tumefaciens LBA4404 로 도입하였다. Agrobacterium tumefaciens-mediated transformation 방법에 의해 Pleurotus eryngii로 형질전환하고 kanamycin함유된 MCM 배지에서 올바른 형질전환체를 선별하였고, 단백질 발현은 SDS-PAGE 및 항원항체 반응에 의한 western blot으로 확인하였다. 페리틴 단백질의 분비 발현은 batch culture 및 20 L airlift type fermenter에서 배양 시간 및 온도와 같은 배양 조건에 의해 최적화되었다. 페리틴 생산을 위한 배양 조건은 MCM 배지에서 25℃ 및 8 일 배양에 의해 최적화되었다. 페리틴 단백질의 양은 정량적 단백질 분석에 의해 2.4 mg/g mycelium으로 측정되었다. 그러나, PR1b (32 amino acid)의 분비서열은 큰느타리버섯 내부의 peptidase에 의해 정확하게 processing되지 않았지만, 페리틴 단백질은 균사체에서 최대로 전체단백질의 24.7% 발현되었고, 배양액에서는 검출되지 않았다. 철 결합 활성은 7.5% non-denaturing gel에서 Perls' staining에 의해 확인되었으며, 다량체 페리틴(24 subunits)이 P. eryngii 균사체에서 형성되었음을 보여준다. 생물학적 활성 측정을 위하여 페리틴을 함유한 분말을 제조하여 육계의 사료 첨가제로서의 사용 가능성에 대해 시험하였으며, 결과적으로 페리틴은 육계의 성장을 촉진하고 사료 효율 및 생산 지수를 향상시키는것으로 확인되었다.

• Applied Biological Chemistry
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• 제36권2호
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• pp.105-110
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• 1993

Enterobacter sp. S45로부터 inulin fructotransferase를 생산, 정제하고 효소적 특성을 조사하였다. 배양상징액의 $0.4{\sim}0.8$ 포화$(NH_4)_2SO_4$ 침전물인 조효소는 DEAE-cellulose column chromatography 및 fast protein liquid chromatography로 정제하였으며 효소의 회수율은 0.9%였고 약 148배의 정제도를 보였다. 정제된 효소는 전기영동상으로 단일 band였으며 분자량은 SDS-PAGE에 의해 42,800으로 나타났다. 이 효소의 최적 pH는 5.5, 최적 온도는 $50^{\circ}C$였으며 $Mg^{2+}$이온은 효소활성을 30% 증가시키나 $Hg^{2+}$, $Cu^{2+}$ 및 $Fe^{3+}$이온들은 활성을 강력히 저해하였다. Inulin에 대한 km 값은 1.4 mM, Vmax 값은 $0.196\;{\mu}mole/min$이었다. 본 효소는 inulin을 fructose 말단으로부터 fructose 두 분자씩 절단, 환상형인 DFA를 생성하며, 그 결과 inulin 분해산물인 GF, $GF_2$, $GF_3$, $GF_4$ 등도 검출되었다. 중합도에 따른 효소활성을 조사해 본 결과 이 효소는 중합도 $4(GF_3)$ 이상의 fructo 올리고당에만 작용하여 $GF_3$는 DFA III와 GF로, $GF_4$는 DFA III와 $GF_2$로 변환시켰다. 또한 본 효소는 sucrose, raffinose 및 melezitose를 기질로서 이용하지 못하므로 invertase 및 ${\alpha}-glucosidase$ 활성이 없는 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제21권8호
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• pp.808-817
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• 2011

Because of its elevated cellulolytic activity, the filamentous fungus Trichoderma harzianum has a considerable potential in biomass hydrolysis applications. Trichoderma harzianum cellobiohydrolase I (ThCBHI), an exoglucanase, is an important enzyme in the process of cellulose degradation. Here, we report an easy single-step ion-exchange chromatographic method for purification of ThCBHI and its initial biophysical and biochemical characterization. The ThCBHI produced by induction with microcrystalline cellulose under submerged fermentation was purified on DEAE-Sephadex A-50 media and its identity was confirmed by mass spectrometry. The ThCBHI biochemical characterization showed that the protein has a molecular mass of 66 kDa and pI of 5.23. As confirmed by smallangle X-ray scattering (SAXS), both full-length ThCBHI and its catalytic core domain (CCD) obtained by digestion with papain are monomeric in solution. Secondary structure analysis of ThCBHI by circular dichroism revealed ${\alpha}$- helices and ${\beta}$-strands contents in the 28% and 38% range, respectively. The intrinsic fluorescence emission maximum of 337 nm was accounted for as different degrees of exposure of ThCBHI tryptophan residues to water. Moreover, ThCBHI displayed maximum activity at pH 5.0 and temperature of $50^{\circ}C$ with specific activities against Avicel and p-nitrophenyl-${\beta}$-D-cellobioside of 1.25 U/mg and 1.53 U/mg, respectively.

• 대한간호학회지
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• 제14권2호
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• pp.93-111
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• 1984

The main purpose of this study is to develop a ratio scale measuring level of pain using Korean pain terms. The specific purposes of this study are to identify the degree of pain of each pain term in each subclass: to classify each subclass in terms of dimensions of pain; and to analyze factors of the Korean pain ratio scale clustering together. One hundred an4 fifty eight pain terms which were originally identified as representative terms and their synonyms were used for data collection. Fifty eight nursing professors ana sixty one medical doctors who have contacted with patients having pain were asked to rate the weight of each pain term on a visual analogue scale. Subclasses in which ranks of pain terms were same f s findings in two previous studies were 1) thermal 3 am 2) cavity pressure, 3) single stimulating pain, 4) radiation pain. and 5) chemical pain. Subclasses in which ranks of pain terms were confused were 1) incisive pressure, and 2) cold pain. Subclasses in which one new pain term was added were 1) inflammatory-repeated pain, 2) punctuate pressure, 3) constrictive pressure, 4) fatigue-related pressure, and 5) suffering-relate4 pain. Subclasses in which two new pain terms were added were 1) traction pressure, 2) peripheral nerve pain, 3) dull pain, 4) pulsation-related pain, 5) digestion-related pain, 6) tract pain, and 7) punishment-related pain. Subclass in which 3 new pain terms were included was fear-related pain. Rating scores of 5 words in 4 subclasses were significantly different between the normal group and the extreme group of subjects in terms of subjective rating. Only one word among 6 words was that newly added to the scale. Rating scores of 12 words in 9 subclasses were significantly different between doctor group and nursing professor group. Among these 12 words, only 3 were those newly added to the scale. In comparison of these 12 words, mean scores of the nursing professors were always 7 to 16 points higher than those of the medical doctors. In the analysis of judgement of subjects in terms of dimensions of pain terms, subclasses of dull pain, cavity pressure, tract pain and cold pain were suggested to be included in the miscellaneous dimension. As a result of factor analysis of the ratings given to 96 pain words using principal components analysis without iteration and with varimax rotation limiting the number of factors to 4, factors of severe pain (factor I) mild-moderate pain (factor II) , causative pain (factor III) and temperature-related pain(factor IV) were extracted with the factor loading above 0.388. When the pain words were re-arranged on the bases of factor loading above 0.368, number of factors decreased to only first two factors. Maximum score of pain word in factor II was 46.17 and the minimum score of the factor I was 45.36. Further studies are needed to identify the validity, reliability, sensitivity and practicability of this ratio scale using patients having various sources of pain.

• 약학회지
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• 제37권5호
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• pp.511-519
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• 1993

The short and variabke transit of drug throught GI tracj and the inter-and intra-subject variations of the transit restrict the sustained drug absorption after oral adminstration. These restrictions may be solved by retaining the dosage forms in the stomach. Then the dosage form will act as a platform which releases the drug slowly and makes the GI absorption occur for a long time. In this study, as the platforms, PVP hydrogels were synthesized by chemical and y-irradiation method in the cylindrical test tube. The chemical method means the synthesis of the hydrogel by heating the mixed solution of N-vinyl-2-pyrrolidone [monomer], acrylated albumin [crosslinking agent], 2, 2'-agobis(2-methylpropionitrile) [initiator] and proxyphylline [drug] at $65^{\circ}C$ for 5 hr. The $\gamma$-irradiation method means the synthesis of the hydrogel by irradiation with $^{60}$ Co $\gamma$-ray of the mixed solution of the monomer, acrylated albumin, and flurbiprofen [drug] at room temperature with total 0.2 Mrad for 3 hr. Our intention is to design the hydrogel tablet (diameter : 1.20 cm, thickness : 0.60 cm) which swells in the gastric fluid after oral administration to such a size that passing through the pylorus could be inhibited during the period of drug release. After releasing drug, the hydrogel should be degraded by the enzymeatic digestion in the stomach, or by hydrolysis and eventually solubilized. Thus, in votro tests were performed to examine the factors that affect swelling and drug release from the PVP hydrogels. Experimental results show that the hydrogels swell to a size larger than the diameter of the pylorus(l.3$\pm$0.7 cm) and the hydrogel prepared by the chemical method is digested by pepsin. But the hydrogel prepared by the $\gamma$-irradiation method was not digested by the pepsin and just collapsed with time. Thus, the swelling of the hydrogel synthesized by $\gamma$-irradiation was independent albumin acrylation time and pepsin concentration. But drug content and radiation dose affected the swelling and drug release kinetics of the hydrogel. Drug release from the hydrigels was prolonged up to about 24 hr. Therefore, it was concluded that by adjusting these factors, the albumin-crosslinked PVP hydrogel synthesized by $\gamma$-irradiation method is expected to be retained in the stomach for up to 60hr and be a potential platform of drugs for long-term GI absorption.

• 유기물자원화
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• 제20권1호
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• pp.71-77
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• 2012

농업 바이오매스의 혐기소화 적용성을 위해 가장 많은 양이 발생하는 볏짚을 원료로 하여 전처리에 따른 볏짚의 가수분해과정에서 가용성 화학적 산소요구량 (SCOD)의 변화 특성을 조사하였다. 전처리 조건으로는 4 종류의 볏짚 크기, 4 종류의 온도, 2 종류의 초음파처리 및 알칼리를 처리하였다. 분해지표인 SCOD 용출량은 입자 크기가 작을수록, 반응 온도가 높을수록, 알카리를 처리하였을 때 높게 나타나 볏짚의 분해가 증진되는 것으로 나타났다. 5% NaOH를 처리한 경우 $35^{\circ}C$에서는 SCOD가 최고 9,000 mg $L^{-1}$로 증가하였으며, $55^{\circ}C$에서는 최고 6,000 mg $L^{-1}$까지 증가하였다가 감소하는 경향을 보였다. 또한 40 kHz의 초음파를 조사하여 3 cm 이하의 크기로 절단된 볏짚의 SCOD를 증진시킬 수 있는것으로 나타났으며, 온도에 관계없이 150 rpm의 교반속도에서 SCOD 용출량이 가장 높게 나타났다.

• 미생물학회지
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• 제37권4호
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• pp.245-252
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• 2001

MLS (macrolide-lincosamide-streptogramin B) 항생제 내성인자 단백질인 Erm 단백질들은 아미노산 서열 중 그 동일성과 유사성이 높아 구조적으로도 동등한 단백질의 한 집단을 형성한다. 최근 X-ray crystallography에 의해 구조가 결정된 ErmC\` 및 ErmAM 단백질의 구조에 근거하여 ErmSF 단백질도 catalytic domain과 substrate binding domain으로 구분하였고 N-terminal end에 존재하는 catalytic domain의 대량생산을 다양한 pET 발현 vector를 사용하여 시도하였다. 그리고 catalytic domain을 coding하는 DNA 절편은 세 종류를 사용하였다: DNA 절편 1은 Met 1부터 Glu 186까지를 coding하고 DNA 절편 2는 Arg 60부터 Glu 186까지의 정보를 가진 DNA이고 DNA 절편 3은 Arg 60부터 Arg 240까지를 encoding하는 DNA이다. 사용된 다양한 발현 vector중에서 pET19b는 DNA 절편 3, pET23b는 DNA 절편 1과 2를 성공적으로 대량생산하였다. 그러나 대량생산된 catalytic domain들은 불용성 단백질 집합체인 inclusion body를 형성하였다. ErmSF catalytic domain들의 용해성 단백질의 생산을 위하여 chaperone GroESL과 Thioredoxin의 동시 발현 및 배양온도를 $22^{\circ}C$로 낮추어 시도했으나 대량 발현된 단백질의 용해에는 도움을 얻지 못하였다.

• Journal of Periodontal and Implant Science
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• 제32권4호
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• pp.865-873
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• 2002

The primary cause of tooth loss after 30 years of age is periodontal disease. Destruction of alveolar bone by periodontal disease is done by bone resorbing activity of osteoclasts. Understanding differentiation and activation mechanism of osteoclasts is essential for controling periodontal disease. The purpose of this study is to identify the possible effects of Vitamin D and cytokines affecting osteoclasts and its precursor cells. Four to six week-old mice were killed and humerus, radius, tibia and femur were removed aseptically and washed two times with Hank's solution containing penicillin-streptomycin and then soft tissue were removed. Bone marrow cells were collected by 22 gauge needle. Cells were cultured in Hank's solution containing 1 mg/ml type II collagenase, 0.05% trypsin, 41mM EDTA. Supernatant solution was removed 5 times after 15 minutes of digestion with above mentioned enzyme solution, and remained bone particles were maintained in alpha-MEM for 15 minutes and $4^{\circ}C$ temperature. Bone particles were agitated for 1 minute and supernatant solution containing osteoclast precursor cells were filtrated with cell stainer. These separated osteoclast precursor cells were dispensed with 100-mm culture dish by $1{\times}10^7$ cells unit and cultured in ${\alpha}$- MEM containing 20 ng/ml recombinant human M-CSF, 30 ng/ml recombinant human soluble osteoclast differentiation factor and 10% fetal calf serum for 2 and 7 days. Total RNA of osteoclast precursor cells were extracted using RNeasy kit. One ${\mu}g$ of total RNA was reverse transcribed in $42^{\circ}C$ for 30 minutes using SuperScriptII reverse transcriptase. Expression of transcribed receptors of each hormone and cytokine were traced with 1 ${\mu}l$ of cDNA solution by PCR amplification. Vitamin D receptor WAS found in cells cultured for 7 days. TNF-${\alpha}$ receptor was found in cells cultured for 2 days and amount of receptors were increased by 7 days. IL-1 type I receptor was not found in cells cultured 2 and 7 days. But, IL-1 receptor type II was found in cells cultured for 2 days. TGF-${\alpha},{\beta}$type I receptor was found in cells cultured 2 and 7 days, and amount of receptors were increased by 7 days of culture. These results implies Vitamin D and cytokines can affect osteoclasts directly, and affecting period in differentiation cycle of osteoclasts is different by Vitamin D and cytokines.

• 한국환경교육학회지:환경교육
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• 제11권2호
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• pp.130-143
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• 1998

This study was conducted as a preliminary step to establish a model for the practical application of environmental education related to food wastes collected from elementary school foodservices. Methods of treatment and present recycling status of food wastes in elementary schools in Kyonggido were surveyed. The consciousness of dieticians who have been serving for elementary school foodservices was also analyzed through the survey questions concerning environmental education for the reduction and recycling of food wastes. The results derived from this survey were as follows: The major portion of food wastes from elementary school foodservices was constituted with vegetables and soup, and an average amount of food wastes per day was highest in June and July. Therefore environmental education related to reduction of wastes was needed in the first semester of school terms, and the possible reduction of food wastes achieved through the proper planning of school foodservice menu was also needed. In most cases food wastes were collected and treated by animal growing farmers or composted by machines in school. In operating composting machines microorganism inoculant was mostly used but dieticians pointed out the problem of a nasty odor, insects, and high energy consumption. This situation means it has not been operated efficiently and suggests an efficiency problem of machine composting in elementary schools because composting itself is based on the aerobic digestion and high temperature fermentation which kills insects and harmful microorganisms. Elementary school dieticians in Kyonggido were aware that food wastes cause main pollution problem, and that food wastes are valuable resources which can be recycled, and recycling of food wastes is inevitable. But more than half of the schools surveyed have not been reused food wastes in school, so a proper model for recycling and reuse of food wastes in school grounds was thought to be needed. Environmental education programs related to food wastes have not been peformed in more than half of the schools surveyed. It was concluded that the following three plans will be helpful to reduce school food wastes. First, environmental education should be enforced, second, teachers' and dieticians' intensive teaching concerning food wastes should be needed, and finally establishment of a model for recycling and reuse of food wastes in school grounds and its application to environmental education would offer a valuable field experience to school students.