• 생명과학회지
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• 제13권3호
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• pp.308-313
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• 2003

식중독 병원균인 장염비브리오균 (V. parahaemolyticus)의 세포외 분비 효소 중 콜라겐분해효소를 발현벡터인 pET-29b에 클로닝시키고 대장균에서 발현시킨 다음, 부분정제하여 그 특성을 조사하였다. V. parahaemolyticus collagenase는 $(NH_4)_2So_4$침전, affinity adsorption, 그리고 Sephacryl S-100 gel filtration 과정을 통하여 부분정제 되었다. 이 collagenase는 73%의 회수율과 43.7의 정제도를 나타내었으며, 전기영동시 분자량은 약 35 kDa로 나타났다. 이 효소의 최적 pH 및 온도는 6~12와 $35^{\circ}C$이었고, 온도안정성 조사에서 $55^{\circ}C$까지는 90% 잔존 찬성을 유지하였으나 $60^{\circ}C$이상에서는 급격하게 효소활성이 실활되었다. 기질특이성조사에서 type I collagen과 콜라겐분해효소의 합성기질로 알려진 Z-GPGGPA에서 gelatin과 casein에 비해 높은 활성을 보이는 것으로 보아 이 효소가 진정한 콜라겐분해효소라는 것을 알 수 있었다.

• Journal of Microbiology
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• 제33권3호
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• pp.244-251
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• 1995

An extracellular protease of Salmonella schottmulleri was purified from culture filtrate by using 0-75% ammonium sulfate precipitation, DEAE Sepharose Fast Flow ion exchange chromatography, Ultrogel HA chromatography and Sephacryl S-200 HR molecular sieve chromatography. To measure enzyme activity, synthetic dipeptide substrate (CBZ-arg-arg-AFC) with low molecular weight was employed as substrate. The molecular weight of the purified enzyme was approximately 80 kDa when determined by gel filtration on Sephacryl S-200 HR and 73 kDa when estimated by SDS-PAGE. The isoelectric point was 5.45. The activity of the purified enzyme was inhibited by metal chelating agesnts such as EDTA and 1.10-phenanthroline. The divalent cations, such as Ca$\^$2+/, Zn$\^$2+/, Fe$\^$2+/, Mg$\^$2+/ enhanced its activity. These results suggested that it was a metalloprotease. It had a narrow pH optimum of 6.5-7.5 with a maximum at pH 7.0 and a temperature optimum of 40.deg.C. It was stable at least for 1 week at 40.deg.C and maintained its activity for 24 hours at 50.deg.C, but it was rapidly inactivated at 65.deg.C. This protease was shown to be sensitive to sodium 50.deg.C, but it was rapidly inactivated at 65.deg.C. This protease was shown to be sensitive to sodium 50.deg.C, but it was rapidly inactivated at 65.deg.C. This protease was shown to be sensitive to sodium 50.deg.C, but it was rapidly inactivated at 65.deg.C. This protease was shown to be sensitive to sodium dodecyl sulfate (SDS) and was inactivated in a dose-dependent manner. However, it was resistant to Triton X-100 and the activity was enhanced to 32.3% with treatment of 0.025% Triton X-100.

• 생명과학회지
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• 제7권2호
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• pp.119-126
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• 1997

Phytase(myo-inositol hexakisphosphate phosphohydro-lase;EC 3.1.3.8)는 흰주 소장 점막으로 부터 분리${\cdot}$정제 하였다. 이 정제된 효소를 Sephacryl S-200 gel filtration방법으로 측정한 분자량으니 160kDa이고, 순도 및 이 효소의 서브유니트를 SDS-polycrylamide gel전기영동법(SDS-PAGE)으로 조사한 결과 서브유니트 구조는 분자량이 10kDa와 90kDa으로 구성된 hetrodimer(이종이량체)임을 알 수 있었다. 그리고 $ MgCl_{2}$ 존재 하에서는 효소 활성이 증가하나 $ZnCl_{2}$, $MnCl_{2}$, 및 EDTA존재 하에서는 효소 활성이 저해되었다. 기질 트이성과 pH범위에서 기질인 phytic acid(inositol-hexakispho-sphate)에 대해 높은 친화력을 보였다. Phytic acid에 대한 Km값은 pH 7.4에서 0.31mM이다. 따라서 흰쥐의 소장 점막 phytase는 주로 inositol의 대사계에서 중요한 역할을 하는 것으로 생각된다.

• 산업식품공학
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• 제13권4호
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• pp.326-334
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• 2009

목이버섯으로부터 항혈전활성과 항혈소판응집활성을 지니는 물질을 추출하여 추출물의 혈행개선활성을 조사하였다. 건조 목이버섯을 0.1 N NaOH, methanol, ethanol 등의 용매를 사용하여 추출하여 각 추출물의 항혈전활성을 activated partial thromboplastin time, thrombin time과 prothrombin time 값으로 측정한 결과 methanol 용해성 분획이 각각 100, 124, 54 s로 조사한 분획 중에서 가장 높은 활성을 나타내었다. 활성 분획을 DEAE-Sepharose CL6B ion exchange column chromatography와 Sephacryl 400-HR gel permeation column chromatography로 정제하였으며 활성물질은 분자량이 150 kDa 이상인 다당류이며 mannose가 주요 구성당으로 되어 있는 xyloglucomannan의 복합다당체인 것으로 확인되었다. 정제된 다당류의 항혈전활성은 thrombin 활성을 저해하기 때문인 것으로 해석되었다.

• 한국식품영양과학회지
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• 제23권3호
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• pp.490-495
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• 1994

Acid phosphatase (EC3.1.3.2) from carrots was partially purified by ammonium sulfate fractionation (30%-80%), Sephacryl S-200 gel filtration, cm-Sepharose CL-6B and DEAE -Sephacel ion exchange chromatography. The optimum ph and temperature of acid phosphatase from carrots were pH 5.5 and 55$^{\circ}C$, respectively. The enzyme was most stable at ph 6.0 and relatively unstable below pH 4.0 . The activation energy of the enayme was determined to be 10.6kcal/mole. The enzyme utilized p-nitrophenyl phosphate as a substrate among tested possible substrates, whereas it hydrolyzed 5' -IMP and 5'-GMP poorly. The Michaelis -Menten constant(Km) of the enzyme with p-nitrophenyl phosphate as a substrate was identified as 0.55mM. Amongtested metal ions and inhibitors, Al+++ Zn++, Cu++ , fluoride, metavanadate and molybdate ions inhibited the enzyme activity drastically.

• 한국식품영양과학회지
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• 제23권5호
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• pp.849-855
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• 1994

Actively growin Excherichia coli(KCTC 1039) cells were treated with paraquat (1, 1'-dimethyl-4, 4'-bipyridili-um dichloride) by cultivating them in the presence of 1.0mM paraquat. The treatment was carried out with or without shaking to understand the effect of oxygen on paraquat action to thebacterial superoxide dismutase (SOd). By the treatment with vigorous shaking , population growth of the organism almostly stopped and specific activities of SOD of the cells drastically decreased. On contrast ot it, the herbicide showed only l limited inhibitory action on bacterial growth and SOD activity by stationary treatment. Proteins prepared from parquat-treated cells divided into two peaks by Sephacryl column chormatogrpahy, while proteins from the intact cells formed a single peak. Cytoplasmic proteins and plasma membrane proteins of intact cells formed separated three peaks by Sephadex G-75 column chormatography. respectively. Among them the second peak disappeared by paraquat treatment , while the third peak became more apparent. Fractions from the first and the third peak showed SOD activity. Paraquat was detected from the same fractions.

• Journal of Plant Biology
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• 제36권4호
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• pp.407-413
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• 1993

해녀콩(Canavalia lineata L. DC) 잎에서 유도한 캘러스를 pH 8인 완충용액에 한 시간 동안 처리하면 pH 6에서 보다 arginase의 활성이 약 두 배로 증가했다. 캘러스에서 얻은 arginase의 조효소액을 Sephacryl S-200 컬럼에서 분획하면 분자량이 각각 380 kD과 179 kD으로 나타났는데 분자량이 큰 arginase의 분획은 pH 8 처리구에서 각각 상대적으로 많이 나타났다. 그리고 pH 6에 0.5 mM Mn2+를 첨가하였을 때도 380 kD arginase의 분획이 크게 나타났으며, pH 6 처리에서 얻은 179 kD arginase 분획에 pH 8 처리를 하면 380 kD 분획으로 쉽게 전이될 수 있었다. pH 6 처리 후 추출한 arginase는 Mn2+의 첨가로 활성이 크게 증가하여 pH 8 처리 후 추출한 arginase와 비슷한 활성을 보이나, pH 8 처리 후 추출한 arginase는 Mn2+의 첨가로 더 이상의 활성증가를 보이지 않았다. Mn2+이 없는 조건에서 두 arginase의 Km값과 Vmax를 조사한 결과, 380 kD arginase는 22 mM과 1.61 $\mu$mole urea.min-1.mg-1 protein, 그리고 179 kD arginase는 30 mM과 0.79 $\mu$mole urea.min-1.mg-1 protein으로 측정되었다.

• Preventive Nutrition and Food Science
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• 제5권3호
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• pp.148-152
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• 2000

Mussel adhesive protein (MAP) was extracted from Korean Mytilus edulis and then partially purified using Sephacryl S-300 gel permeation chromatography and reversed-phase high performance liquid chromatography. As an indicator of adhesiveness, is 3,4-dihydroxyphenylalanine (DOPA) content was determined. Its DOPA/protein ratio of 0.19 was higher than those of other reports, indicating a good adhesive. The partially purified MAP was confirmed by acid-urea polyacrylamide gel electrophoresis using cetylpiridinium bromide as a cationic detergent. Sea mussel hydrolysates were prepared using three commercial proteases to provide value-added functional materials and their angiotensin converting enzyme (ACE) inhibitory activities were determined. Among hydrolysates of sea mussel, Protamex was the best and further purification would improved ACE inhibitory activity.

• BMB Reports
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• 제32권2호
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• pp.147-153
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• 1999

Previously, we reported that the prothrombin kringle 2 (fragment 2), induced by LPS administration into rabbit, inhibited bFGF-stimulated BCE cell growth (Lee et al., 1998). In this study, we cloned and overexpressed the kringle 2 domain of rabbit and human prothrombin as a fusion protein with the pelB leader sequence in E. coli using the T7 promoter. The fusion protein was cleaved during translocation into the peri plasmic space, and cleaved recombinant protein was readily isolated from whole cell lysate by DEAE-Sepharose and Sephacryl S-200 gel filtration chromatography. Both the recombinant rabbit and human prothrombin kringle 2 showed very similar biochemical and functional characteristics to the rabbit prothrombin kringle 2 purified from rabbit serum, in terms of abnormal electrophoretic migration and endothelial cell growth inhibitory activity.

• 미생물학회지
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• 제24권2호
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• pp.119-126
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• 1986

A periplasmic endoprotease, named protease Pi, was purified to homogeneity from Escherkchia coli by conventional procedure with insulin as substrate. This enzyme degrades insulin and glucagon to trichloroacetic acid-soluble meterials, but shows little or no hydrolysis of bovine serum albumin, casein or globin. Its molecular weight was 110, 000 when determined by gel filtration on Sephacryl S-300 and was 105, 000 when estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Thus, it appears to be single polypeptide. This snzyme is metalloprotease, since it is completely inhibited by o-phenanthroline and can be activated by addition of divalent metal cations, such as $Mg^{2+}\;and\;Co^{2+}$. It is destinct from protease Ci, a cytoplasmic insulin degrading enzyme, since protease Pi is localized to the periplasm. Since protease Pi selectively degrades GTP cyclohydrolase I, it appears to play a role in the regulation of pteridine biosynthesis.