• 한국임상수의학회지
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• 제31권5호
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• pp.457-460
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• 2014

뇌경색으로 진단한 소형견 3 마리의 자기공명영상 (MRI)을 평가하였다. 뇌경색은 소뇌, 시상, 혹은 다발성으로 발생하였다. 뇌경색은 병변의 경계가 비교적 뚜렷하고, 균질하게 T1강조영상에서 저신호, T2강조영상에서 고신호를 나타내었다. 조영증강효과는 없거나, 병변의 주변부로 미약하게 조영증강효과가 나타나기도 했다. 확산강조영상 (DWI)에서는 고신호로 나타나며 이 부위의 겉보기확산계수 (ADC)는 감소되었다.

• Journal of Microbiology
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• 제44권2호
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• pp.185-191
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• 2006

The photosynthetic bacterium, Rhodospirillum rubrum S1, when grown under anaerobic conditions, generated three different types of catalases. In this study, we purified and characterized the highest molecular weight catalase from the three catalases. The total specific catalase activity of the crude cell extracts was 88 U/mg. After the completion of the final purification step, the specific activity of the purified catalase was 1,256 U/mg. The purified catalase evidenced an estimated molecular mass of 318 kDa, consisting of four identical subunits, each of 79 kDa. The purified enzyme exhibited an apparent Km value of 30.4 mM and a Vmax of 2,564 U against hydrogen peroxide. The enzyme also exhibited a broad optimal pH $(5.0{\sim}9.0)$, and remained stable over a broad temperature range $(20^{\circ}C{\sim}60^{\circ}C)$. It maintained 90% activity against organic solvents (ethanol/chloroform) known hydroperoxidase inhibitors, and exhibited no detectable peroxidase activity. The catalase activity of the purified enzyme was reduced to 19 % of full activity as the result of the administration of 10 mM 3-amino-1,2,4-triazole, a heme-containing catalase inhibitor. Sodium cyanide, sodium azide, and hydroxylamine, all of which are known heme protein inhibitors, inhibited catalase activity by 50 % at concentrations of $11.5{\mu}M,\;0.52{\mu}M,\;and\;0.11{\mu}M$, respectively. In accordance with these findings, the enzyme was identified as a type of monofunctional catalase.

• Applied Biological Chemistry
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• 제41권5호
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• pp.355-362
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• 1998

병아리콩 근류의 호스트부분에서 플라스티드에 존재하는 것으로 추정되는 포스포프룩토오스 키나아제(EC 2.7.1.11; PFK)을 순수분리 정제하고, 정제된 단백질 분자량이 220 kDa인 비당단백질(N-linked)이다. SDS-PAGE와 Western blot의 결과는 정제된 효소가 4개의 55 kDa subunit로 이루어져 있음을 지적하고 있다. 이 효소는 pH 8에서 최적활성으로 날카로운 곡선을 나타내고 있으며, 최적 pH 8과 생리적으로 비슷한 pH 7에서 Fru-6-P 및 nucleoside triphosphate 기질에 Michaelis-Menten kinetics을 나타냈다. MgATP가 뉴크레오 삼인산중에 가장 효율적인 인산기 공여체로서 나타냈다. 포스포엔롤피루베이트는 마이너 형태의 PFK 활성에 가장 강력한 억제자이며, 또한 이 효소는 3-포스포글리세레이트와 2-포스포글리세레이트에 의해 강하게 억제된다. 마이너 형태의 PFK는 KCl, NaCl등 Pi에 의해 약하게 활성이 증진되지만, 높은 농도에서는 억제자로서 작용한다.

• Journal of Microbiology and Biotechnology
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• 제24권4호
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• pp.545-555
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• 2014

It has been previously demonstrated that laccases exhibit great potential for use in several industrial and environmental applications. In this paper, two laccase isoenzyme genes, lccB and lccC, were cloned and expressed in Pichia pastoris GS115. The sequence analysis indicated that the lccB and lccC genes consisted of 1,563 and 1,584 bp, and their open reading frames encoded 520 and 527 amino acids, respectively. They had 72.7% degree of identity in nucleotides and 86.7% in amino acids. The expression levels of LccB and LccC were up to 32,479 and 34,231 U/l, respectively. The recombinant laccases were purified by ultrafiltration and $(NH_4)_2SO_4$ precipitation, showing a single band on SDS-PAGE, which had a molecular mass of 58 kDa. The optimal pH and temperature for LccB were 2.0 and $55^{\circ}C$ with 2,2'-azinobis-[ 3-ethylbenzthiazolinesulfonic acid (ABTS) as a substrate, whereas LccC exhibited optimal pH and temperature at 3.0 and $60^{\circ}C$. The apparent kinetic parameters of LccB were 0.43 mM for ABTS with a $V_{max}$ value of 51.28 U/mg, and the Km and $V_{max}$ values for LccC were 0.29 mM and 62.89 U/mg. The recombinant laccases were able to decolorize five types of dyes. Acid Violet 43 (100 g/ml) was completely decolorized by LccB or LccC (2 U/ml), and the decolorization of Reactive Blue KN-R (100 g/ml) was 91.6% by LccC (2 U/ml). Thus, the study characterizes useful laccase isoenzymes from T. versicolor that have the capability of being incorporated into the treatment of similar azo and anthraquinone dyes from dyeing industries.

• Journal of Microbiology and Biotechnology
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• 제24권1호
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• pp.19-25
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• 2014

An extracellular agarase was purified from Bacillus sp. BI-3, a thermophilic agar-degrading bacterium isolated from a hot spring in Indonesia. The purified agarase revealed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with an apparent molecular mass of 58 kDa. The optimum pH and temperature of the agarase were 6.4 and $70^{\circ}C$, respectively. The activity of the agarase was stable at high temperatures, and more than 50% activity was retained at $80^{\circ}C$ for 15 min. Furthermore, the enzyme was stable in the pH range of 5.8-8.0, and more than 60% of the residual activity was retained. Significant activation of the agarase was observed in the presence of $K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$, and $Sr^{2+}$; on the other hand, $Ba^{2+}$, $Zn^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Co^{2+}$, $Fe^{2+}$, and EDTA inhibited or inactivated the enzyme activity. The components of the hydrolytic product analyzed by thin-layer chromatography showed that the agarase mainly produced neoagarobiose. This study is the first to present evidence of agarolytic activity in aerobic thermophilic bacteria.

• Fisheries and Aquatic Sciences
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• 제17권1호
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• pp.75-84
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• 2014

To determine a suitable dietary protein/lipid (CP/CL) ratio in the early juvenile stages of hybrid porgy ($F_1$), female red sea bream (RSB) ${\times}$ male black sea bream, five diets with various CP/CL ratios-60/7, 55/12, 51/17, 46/23, and 41/28-were prepared and provided to juveniles in triplicate. At the smaller juvenile stage, $F_1$, weighing 0.32 g, a significantly higher specific growth rate (SGR) and feed efficiency (FE) were seen with 60/7 and 55/12 diets. However, in RSB weighing 0.26 g, SGR and FE were higher with the 60/7 diet than the other diets at $21^{\circ}C$. At the larger juvenile stage, $F_1$, weighing 3.7 g, there was no significant difference in SGR or FE among the diets, but RSB weighing 4.0 g fed 60/7, 55/12, and 51/17 diets had higher SGR and FE than 46/23 and 41/28 diets at $24^{\circ}C$. Moreover, survival and apparent nutrient retention of $F_1$ at both stages were significantly higher than those in RSB. These results indicate that both $F_1$ and RSB weighing ca. 0.3 g require a higher dietary CP/CL than those weighing ca. 4 g. Additionally, $F_1$ in both trials showed the suitability of a lower dietary CP/CL than RSB, indicating that mass production of $F_1$ juveniles will be more economical than RSB.

• 한국임상약학회지
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• 제18권1호
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• pp.60-67
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• 2008

This study aimed to compare a microparticle enzyme immunoassay (MEIA) with a liquid chromatography-tandem mass spectrometry (LC/MS/MS) technique for the measurement of tacrolimus concentrations in adult liver transplant recipients, to investigate how the assay choice influenced the population pharmacokinetics of tacrolimus and to identify patient characteristics that affected pharmacokinetic parameters in each assay. Tacrolimus concentrations from 29 liver (n=52 paired-samples) transplant recipients measured by both MEIA and LC/MS/MS were used to evaluate the performance of these methods in the clinical setting. Tacrolimus pharmacokinetics was studied independently using MEIA and LC/MS/MS data in 70 adult patients using a population approach performed with NONMEM. Patient characteristics which influenced pharmacokinetic parameters in each assay were compared. The relation between LC/MS/MS and MEIA measurements was best described by the regression equation MEIA=1.465*LC/MS/MS-1.336 (r=0.91). Multiple linear regression analysis showed significant inverse relationships between assay difference and hematocrit (Hct) (p<0.025) in liver graft recipients. In MEIA, the population estimate of tacrolimus CL/F and apparent volume of distribution (Vd/F) were found to be 10.1 L/h and 226 L, and in LC/MS/MS, 13 L/h and 305 L respectively. Neither patient's age, weight, gender, grafted hepatic weight, albumin concentration, nor markers of liver function influenced tacrolimus CL/F The final model of CL/F was found to be 10.1+(Hct/Hct mean)$^{12.0}$ in MEIA and 13+(1+Hct/578) in LC/MS/MS indicating that CL/F was influenced by hematocrit.

• BMB Reports
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• 제37권4호
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• pp.466-473
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• 2004

A new acid deoxyribonuclease (DNase) was purified from the cultured mycelia of Cordyceps sinensis, and designated CSDNase. CSDNase was purified by $(NH_4)_2SO_4$ precipitation, Sephacryl S-100 HR gel filtration, weak anion-exchange HPLC, and gel filtration HPLC. The protein was single-chained, with an apparent molecular mass of ca. 34 kDa, as revealed by SDS-PAGE, and an isoelectric point of 7.05, as estimated by isoelectric focusing. CSDNase acted on both double-stranded (ds) and single- stranded (ss) DNA, but preferentially on dsDNA. The optimum pH of CSDNase was pH 5.5 and its optimum temperature 55. The activity of CSDNase was not dependent on divalent cations, but its enzymic activity was inhibited by high concentration of the cation: $MgCl_2$ above 150 mM, $MnCl_2$ above 200 mM, $ZnCl_2$ above 150 mM, $CaCl_2$ above 200 mM, NaCl above 300 mM, and KCl above 300 mM. CSDNase was found to hydrolyze DNA, and to generate 3-phosphate and 5-OH termini. These results indicate that the nucleolytic properties of CSDNase are essentially the same as those of other well-characterized acid DNases, and that CSDNase is a member of the acid DNase family. To our knowledge, this is the first report of an acid DNase in a fungus.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2004년도 추계학술대회
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• pp.153-164
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• 2004

The growing importance of product quality is becoming more and more daily apparent as we enter the age of globalization around the world. And the product safety is getting more focus as well as product quality. As a result, many domestic companies are putting a lot of emphasis on safety measures and management activities and these companies' products are mainly superior to other companies' product. When we separate the product quality procedure into 3 steps, i.e. quality secure-quality confirm-quality guarantee, of course the 1st step is the most important, but also 2nd step of product quality confirm process is important. And in mass production environment, sampling inspection is more desirable than the $100\;\%$ inspection procedure. As a part of globalization trend, KS system is also being revised and reestablished based on ISO, IEC, etc. which are based on international standard. Conventional KS sampling inspection standards were in many areas quite different from ISO sampling standards, only KS A 3102, 3104, 3151 are left and the rest become obsolete, and even the ones that are still around are planned to the gone step by step. It has been already 3 years since the new KS A ISO $2859-0\sim3$ sampling inspection process has been established which the abolition of the popular KS A 3101, KS A 3105, KS A 3109, yet the implementation rate is very slow. This study will attempt to analyze the new KS A ISO 2859-2 and KS A ISO 2859-3, and try to understand the difference as that the new standard can be easily understood and used widely among companies, by using examples. Our attempt is to help implement with the companies with active safety involvement but the final result can be spread among other companies as well in the near future.

• 한국미생물·생명공학회지
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• 제29권1호
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• pp.50-55
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• 2001

B. subtilis cx1이 생산하는 박테리오신(BSCX1)을 부분 정제하고 특성을 규명하였다. BSCX1은 pH 안정성 실험에서 pH 2.5~9.5 구간에서도 안정되게 항균활성을 유지하였다. 각종 효소에 대한 안정성 실험에서는 protease, trypsin, proteinase K, 그리고 carboxypeptidase로 처리하였을 때는 완전히 항균활성이 사라졌고, $\alpha$-amylase, lipase, aminopeptidase는 항균활성에 영향을 미치지 못하였다. 이상의 결과로 본 항균물질이 단백질계열의 물질이며 당이나 지질 결합은 항균활성에 큰 영향을 미치지 않는 것으로 추정되었다. 그러나 열에는 불안정하여 $60^{\circ}C$이상에서는 15분 안에 완전히 그 항균활성을 상실하였으며 $50^{\circ}C$ 에서는 15분만에 역가의 50%가 실활 되었다. 이에 반하여 저온에서는 무척 안정하여 $-20^{\circ}C$와 $-70^{\circ}C$에서 수개월간 보관하여도 여전히 항균활성을 그대로 유지하였다. Tricin-SDS-PAGE를 통하여 BSCX1의 분자량은 약 9,500 dalton으로 확인되었ekl. BSCX1은 pH2.5에서 9.5에 이르는 넓은 pH 영역에서 그 활성을 유지하므로, 기존에 개발된 nisin이나 유산균 유래의 항균물질이 pH 안정성이 떨어진다는 단점을 보완할 수 있는 생물학적 식품보존제로서의 개발 가능성을 높이 시사하였다.