• Journal of Microbiology and Biotechnology
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• 제20권12호
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• pp.1647-1652
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• 2010

Autophagy refers to the bulk degradation of cellular proteins and organelles through an autophagosome and plays a pivotal role in the development, cellular differentiation, aging, and elimination of aberrant structures. A failure of autophagy has been implicated in a growing list of mammalian disease states, including cancer and cardiomyopathy. Two ubiquitin-like systems are highly involved in autophagy, especially in the formation of autophagosomes. Here, we purified and characterized Atg7 (an E1-like enzyme), and Atg3 and Atg10 (E2-like enzymes) in order to gain an insight into the role played by ubiquitin-like systems in the formation of autophagosomes. Interestingly, we observed that Atg7 forms a homodimer to construct an active conformation, unlike other E1-like enzymes. Although Atg3 was detected as a monomer under physiological conditions, Atg10 existed in an oligomeric form, indicating that the mechanism by which Atg10 functions may differ from that of Atg3.

• Journal of Microbiology
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• 제37권4호
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• pp.224-228
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• 1999

Benzaldehyde dehydrogenase (BZDH), an enzyme involved in the degradation of toluene and xylenes, is encoded by the phnN gene of Pseudomonas sp. strain DJ77. We determined the nucleotide sequence of a DNA fragment of 1,803 base pairs which included the phnN gene. The fragment contained an open reading frame of 1,506 base pairs to accommodate th 55 kDa sized enzyme encoding BZDH. The enzyme efficiently oxidized benzaldehyde, salicylaldehyde, m-tolualdehyde and ps-tolualdehyde.

• Journal of Microbiology and Biotechnology
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• 제32권5호
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• pp.663-671
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• 2022

The saccharification of cellulose and hemicellulose is essential for utilizing lignocellulosic biomass as a biofuel. While cellulose is composed of glucose only, hemicelluloses are composed of diverse sugars such as xylose, arabinose, glucose, and galactose. Sulfolobus acidocaldarius is a good potential candidate for biofuel production using hemicellulose as this archaeon simultaneously utilizes various sugars. However, S. acidocaldarius has to be manipulated because the enzyme that breaks down hemicellulose is not present in this species. Here, we engineered S. acidocaldarius to utilize xylan as a carbon source by introducing xylanase and β-xylosidase. Heterologous expression of β-xylosidase enhanced the organism's degradability and utilization of xylooligosaccharides (XOS), but the mutant still failed to grow when xylan was provided as a carbon source. S. acidocaldarius exhibited the ability to degrade xylan into XOS when xylanase was introduced, but no further degradation proceeded after this sole reaction. Following cell growth and enzyme reaction, S. acidocaldarius successfully utilized xylan in the synergy between xylanase and β-xylosidase.

• 한국잠사곤충학회지
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• 제36권1호
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• pp.44-52
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• 1994

산소정련으로 기준 정련방법이 대체될 수 있다. 마르세일비누(25% o.w.f)로 1.5시간 동안 자등하는 기존 방법으로 정련하는 경우 연감율이 24% 내외인데 비해 효소(10% o.w.f)로 5$0^{\circ}C$에서 1시간 정련하면 22%의 연감율을 얻었다. 산소정련은 기존 방법에 비해 처리온도를 현저히 낮출 수 있고 처리시간을 단축할 수 있으며 이러한 방법으로 실크의 광택과 부드러운 촉감을 얻을 수 있었다. 산소의 처리량을 절감하기 위한 Pad-store 방법이 규명되었는데 이 방법에서 효소처리 농도를 0.5%로 낮추고 5$0^{\circ}C$에 5~6시간 정련하면 연감율이 22%로 되었다. Pad-store 방법은 위의 용액처리 방법에 비하여 효소처리량을 20배 절감할 수 있었지만 처리견의 강력이 감소되므로서 5$0^{\circ}C$에서 7~8시간 처리로 정련견의 취화가 일어난것으로 보인다. Pad-store 방법에서 견의 강력이 감소된 것은 정련과정중 효소가 작용하는 부위에서 교반작용이 없기 때문이며 실크의 취화는 시간보다 온도의 영향이 큰 것으로 생각된다.

• 한국균학회지
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• 제14권1호
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• pp.79-84
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• 1986

Ganoderma lucidum의 개체배양물(個體培養物)로 부터 얻은 cellulase를 ammonium sulfate fractionation으로 조정제(組精製)한 후(後) 이 효소(酵素)의 기본적(基本的)인 특성(特性)을 조사(調査)하였다. 이 효소(酵素)의 최적작용(最摘作用) pH와 온도(溫度)는 각각 pH $4.0{\sim}7.0$사이와 $50^{\circ}C$ 이하(以下)의 온도(溫度)에서는 비교적(比較的) 안정(安定)하였다. CMC-2Na분해(分解)에 대한 activation energy는 6.2 Kcal/mole이었다. $Mg^{++},\;Co^{++}$에 의해서 효소활성(酵素活性)이 증가(增加)되었으나 $Hg^{++}$에 의해서는 저해(沮害)되었다. 한편 본(本) 효소활성(酵素活性)은 SDS에 의해서 약 27%저해(沮害)된 것을 제외(除外)하고는 여러가지 chemical reagents에 의해서는 아무런 영향(影響)을 받지 않았다. 본(本) 효소(酵素)의 CMC-2Na에 대한 Km치(値)는 2.4 mg/ml였으며 CMC-2Na 이외(以外)에 천연(天然) cellulose에도 작용(作用)을 하였다.

• 한국연초학회지
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• 제27권1호
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• pp.75-82
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• 2005

This work investigated biodegradability for the cellulose acetate, carbon dual, paper and web used to cigarette filter materials by soil test. Also, because of demanded a lot of the time and effort in case of soil test, the possibility of biodegradation by enzyme was studied. The evaluation of degradation for the filter materials by soil test was examined with the naked eye, electron microscopy and weight loss. The biodegradability according to the filter materials was represented in the order of paper > web > carbon dual > cellulose acetate without relating to the evaluation methods. Experiment of biodegradability by the cellulase(E C 3.2.1.4, Trichoderma viride) among the several biodegradability enzymes was demanded reaction time of the $5\~10$ hours and represented the same result with that of soil test.

• 한국미생물·생명공학회지
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• 제19권1호
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• pp.52-56
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• 1991

부분 정제한 Pseudomonas spp. Endo-inulinase와 Bacillus spp. Exo-inulinase를 13:1의 비율로 혼합 사용하여 inulin을 가수분해한 결과, 단독으로 사용했을 때에 비해 약 1.6배의 현저한 가수분해율의 상승효과를 얻었다. 혼합효소는 반응온도 $55^{\circ}C$, 반응액의 pH 6.0 및 각 0.5mM 농도와 $Mn^{2+}$와 $CO^{2+}$이 존재하는 반응조건하에서 가장 높은 가수분해율을 보였으며 이때 최종 가수분해 산물인 fructose의 생산량은 84를 나타내었다.

• Archives of Pharmacal Research
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• 제29권12호
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• pp.1179-1186
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• 2006

Cross-linked starch microspheres were prepared using different kinds of cross-linking agents. The influence of several parameters on morphology, size, swelling ratio and drug release rate from these microspheres were evaluated. These parameters included cross-linker type, concentration and the duration of cross-linking reaction. Microspheres cross-linked with glutaraldehyde had smooth surface compared with those prepared with epichlorhydrine or formaldehyde. The particle size increased with increasing the cross-linking time and increasing the drug loading. Swelling ratio of the particles was a function of cross-linker type but not the concentration or time of cross-linking. Drug release from starch microspheres was measured in phosphate buffer and also in phosphate buffer containing a-amylase. Results showed that microspheres cross-linked with epichlorhydrine released all their drug content in the first 30 minutes. However, cross-linking of the starch microspheres with glutaraldehyde or formaldehyde decreased drug release rate. SEM and drug release studies showed that cross-linked starch microspheres were susceptible to the enzymatic degradation under the influence of alpha-amylase. Changing the enzyme concentration from 5000 to 10,000 IU/L, increased drug release rate but higher concentration of enzyme (20,000 IU/L) caused no more acceleration.

• Fisheries and Aquatic Sciences
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• 제18권4호
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• pp.349-357
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• 2015

To reutilize fisheries waste, we isolated a bacterial strain from a coastal area located in Busan. It was identified as Bacillus licheniformis TK3-Y. Using plate assay and 500-mL flask experiments, we found that the isolate simultaneously possessed cellulolytic, proteolytic, and lipolytic activities with salt tolerance. 10% (v/v) inoculums, were used to examine the biodegradation characteristics of the TK3-Y strain on carboxymethylcellulose, skim milk, and olive oil media. The optimum conditions for pH, temperature, agitation speed, and NaCl concentration on each 1% substrate were 6, $50^{\circ}C$, 180 rpm, and 17.5%, respectively. Under optimal conditions, the TK3-Y strain showed 1.07 U/mL cellulolytic, 1,426 U/mL proteolytic, and 6.45 U/mL lipolytic activities. Each enzyme was stable within a range of 17.5-35% NaCl. Therefore, the salt tolerance ability of strain TK3-Y was superior to other related strains. In degradation of a mixed medium containing all three substrates, both the cellulolytic and proteolytic activities were somewhat lower than those on each single substrate, while the lipolytic activity was somewhat higher. From the above results, the TK3-Y strain appears to be a good candidate for use in the efficient treatment of fisheries waste in which components are not collected separately.

• Archives of Pharmacal Research
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• 제9권2호
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• pp.87-91
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• 1986

In attempt to develop a drug delivery system using serum albumin microspheres, bovine serum albumin microspheres containing antitumar agent. Cytarabine, were prepared. The shape, surface characteristics, size distribution, behavior of in vivo distribution, drug release behavior, and degradation of albumin microsphers in animal liver issue homogenate and proteolytic enzyme were investigated. The shape of albumin microspheres was spherical and the surface was smooth and compact. The size distribution of the albumin microspheres was effected by dispertion forces during emulsification and albumin concentration. Distribution of albumin microspheres after imtravenous administration in rabbit was achieved immediately. In vitro, albumin microsphere matrix was so hard that it retained most of cytarabine except initial burst during the first 10 minutes, and the level of drug release during the initial burst was affected by heating temperature, drug/albumin microsphere matrix was so hard that it retained most of cytarabine except initial burst during the first 10 minutes, and the level of drug release during the initial burst was affected by heating temperature, drug/albumin concentration ratio and size distribution. After drug release test, the morphology of albumin microspheres was not changed. Albumin microsphere matrix was degraded by the animal liver issue homogenate and proteolytic enzyme. The degree of degradation was affected by heating temperature.