• 한국미생물·생명공학회지
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• 제30권1호
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• pp.26-32
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• 2002

저염상태에서 속성 발효를 통한 멸치 어간장의 대량 생산을 위하여 시중 어간장에서 단백질 분해효소 생산이 우수한 균주를 분리 동정하여, B. amyloliquefaciens HTP-8로 명명하였다. 효소생산을 위한 배양 최적온도, 초기 pH, 그리고 배양시간은 각각 $30^{\circ}C$, pH 7.0과 3일이었다. Jar fermenter 배양시 pH를 7.0으로. 조절한 경우가 조절하지 않은 경우에 비해 효소활성이 최대에 이르는 시간이 단축되었다. 효소의 부분정제는 조효소액을 80% ammonium sulfate에 의한 염석과 CM-Sephadex C-50을 이용하여 정제한 결과, 수율이 0.4%, 정제배수가 43.0배였다. 정제효소의 최적 pH와 온도는 pH 10.0과 $50^{\circ}C$였으며, pH 7.0~l2.0의 pH 범위와 $40^{\circ}$ 이하에서 안정하였다. 금속이온 중 $Ag^{＋}$ /, $Ba^{2＋}$ /에 의하여 효소활성이 저해되었다. 한편, 본 효소는 PMSF에 의하여 선택적으로 활성이 억제됨으로써 활성부위에 serine을 가진 serine protease에 속하는 것으로 판단되었다.

• 한국미생물·생명공학회지
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• 제18권4호
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• pp.344-351
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• 1990

계명활성제 내성이 있으면서 호알카리성인 protease를 생산하는 미생물을 토양에서 분리하였다. 분리된 미생물을 형태적, 생리학적, 화학분류학적 및 5S RNA 분석으로 동정한 결과 Bacillus sp.인 것으로 판명되었다. 호알카리성 protease는 황산암모늄 분획, DEAE-Cellulose, CM-Cellulose, Sephadex G-100 column chromatogrphy로 분리, 정제하였다. 정제된 호알카리성 protease는 casein에 대하여 pH6.0에서 11.0 사이에서 안정성을 나타내었다. 분리된 효소의 작용 최적 온도는 $55^{\circ}C$이었다. 이 효소는 diisopropyl fluorophosphate(DFP)로 완전히 불활성화되는 것으로 보아 serine protease로 추정되며 계면활성제의 존재하에서도 안정하였다.

• 한국균학회지
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• 제33권2호
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• pp.69-74
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• 2005

민자주방망이버섯으로부터 분리한 혈전용해효소의 비활성은 22.78 U/mg 이었으며, fibrin를 직접 용해하는 fibrinolytic enzyme 이었다. 15번째까지 N-terminal amino acid 서열 분석 결과, Tyr-Pro-Ser-Pro-Ser-His-Gln-Thr-Ala-Val-Asn-Ala-Ile-Ile-X로 지금까지 발표되지 않은 새로운 효소였다. 분자량은 34 KDa 이고 pH 7.0 부터 pH 9.5의 넓은 영역에서 높은 활성을 나타내는 alkaline protease 였으며, $55^{\circ}C$에서 가장 큰 활성을 보이는 이 효소는 serine protease 저해제인 phenylmethylsulfonyl fluoride를 첨가한 경우 효소의 활성이 전혀 나타나지 않는 것으로 미루어 높은 혈전용해 활성을 갖는 새로운 serine protease로 생각된다. 또한 $Hg^{2+}$의 금속이온을 첨가한 경우에도 효소의 활성은 완전히 사라졌다.

• 미생물학회지
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• 제30권6호
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• pp.501-506
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• 1992

An alkalophilic Vibrio sp. RH530 showing high proteolytic activity was isolated form soil samples by enrichment culture. The activity staining using gelatin SDS- polyacrylamide gel electrophoresis (PAGE ) revealed that the strain produced an alkaline major protease (Apr B) with a size of 27 kDa, and at least six minor proteases. The apparent sizes of four of the minor proteases were approximately 45, 28, 22 and 19 kDa. Apr B and five of the minor proteases were inhibited by serine protease inhibitors including PMSF and DFP, suggesting that they are serine proteases. One of the minor proteases was inhibited by metalloprotease inhibitors, not by serine protease inhibitors, indicating it to be a metalloprotease. Furthermore, the activities of Apr B and Prt 3 were not inhibited by SDS in the reaction mixture. The production of Apr B and some of the minor proteases was specifically affected by culture temperature (30 to 37.deg.C) and pH (7 to 10). The production of Apr B. Prt 2, Prt 5 and Prt 6 was mainly affected by culture temperature, while Prt 4 by culture pH. Prt 1 and Prt 3 were not affected by neither of these factors.

• BMB Reports
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• 제33권2호
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• pp.112-119
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• 2000

Three kinds of serine protease inhibitors, members of the Bowman-Birk trypsin inhibitor, were purified from Dolichos lablab seeds and named Dolichos protease inhibitor 1, 2 and 3 (DI-1, DI-2 and DI-3), respectively. Each inhibitor showed a single band with gel mobility at around 15.9, 12.1 and 14.6 kDa on 20% SDS-PAGE under reducing conditions. To characterize inhibitory specificity, the inhibition constant (Ki) for these inhibitors was measured against several known serine proteases. All three Dolichos protease inhibitors (DI-1, DI-2 and DI-3) inhibited the activity of trypsin and plasmin, but had no effect on thrombin and kallikrein (either for human plasma kallikrein or for porcine pancreas kallikrein). DI-1 inhibited chymotrypsin most effectively (Ki = $3.6{\times}10^{-9}\;M$), while DI-2 displayed inhibitory activity for porcine pancreatic elastase (Ki = $6.2{\times}10^{-8}\;M$). Pre-treatment of the 33 mg/kg of DI-mixture (active fractions from $C_{18}$ open column chromatography that included DI-1, DI-2 and DI-3) inhibited the induction of pseudomonal elastase-induced septic hypotension and prevented an increase in bradykinin generation in pseudomonal elastase-treated guinea pig plasma. Also, the increase of kallikrein activity, by injection of pseudomonal elastase, was inhibited by the pretreatment of the DI-mixture in a guinea pig. Since the DI-mixture had no inhibitory effect on kallikrein activity when Z-Phe-Arg-MCA was used as a substrate in vitro, its inhibitory activity in the pseudomonal elastase-induced septic hypotension model might not be due to a direct inhibition of plasma kallikrein in the activation cascade of the Hageman factor and prekallikrein system. These results suggest that the Dolichos DI-mixture might be used as an inhibitor in pathogenic bacterial protease-induced septic shock.

• Journal of Microbiology and Biotechnology
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• 제32권1호
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• pp.99-109
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• 2022

This study is the first report on production and characterization of the enzyme from an Ornithinibacillus species. A 4.2-fold increase in the extracellular protease (called L9^T) production from Ornithinibacillus caprae L9^T was achieved through the one-factor-at-a-time approach and response surface methodological optimization. L9^T protease exhibited a unique protein band with a mass of 25.9 kDa upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This novel protease was active over a range of pH (4-13), temperatures (30-80℃) and salt concentrations (0-220 g/l), with the maximal activity observed at pH 7, 70℃ and 20 g/l NaCl. Proteolytic activity was upgraded in the presence of Ag⁺, Ca²⁺ and Sr²⁺, but was totally suppressed by 5 mM phenylmethylsulfonyl fluoride, which suggests that this enzyme belongs to the serine protease family. L9^T protease was resistant to certain common organic solvents and surfactants; particularly, 5 mM Tween 20 and Tween 80 improved the activity by 63 and 15%, respectively. More importantly, L9^T protease was found to be effective in dehairing of goatskins, cowhides and rabbit-skins without damaging the collagen fibers. These properties confirm the feasibility of L9^T protease in industrial applications, especially in leather processing.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.515-521
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• 1994

A bacterial strain, which showed the high protease activity at low temperature and the high tolerance for the surfactant, was isolated from soil and identified as Xanthomonas sp. YL-37. The optimal temperature, initial pH, and cultivation time for the production of the alkaline protease by Xanthomonas sp. YL-37 were 20$\circC , 11.0, and 84 hours, respectively. In the jar fermenter culture of Xanthomonas sp. YL-37, the alkaline protease activity was about 15,000 DU/ml/-broth after cultivating for 108 hours. The optimal pH and temperature for the protease activity were 70$\circC and 11.0, respectively. The protease was relatively stable at the pH range of 7.0~12.0 and at the temperatures below 50$\circC . The protease activity at 20$\circC was about the level of 40% of its activity at 70$\circC . The enzyme was suggested as a serine protease because the enzyme activity was inhibited by phenylmethane sulfonyl fluoride, a serine modifier.

• Parasites, Hosts and Diseases
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• 제27권3호
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• pp.161-170
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• 1989

Toxeplasma의 추출액을 3H-casein을 기질로 반응시켰을 때, pH 6.0과 PH 8.5에서 casein을 분해하였으며, pH 6.0에서는 cysteinyl protease의 억제제 인 iodoacetamide(rAh)에 의해 억제되 었고, 활성제 인 dithiothreitol (DTT)에 의해 환성이 증가하였다. 또 pH 8.5에서는 serine protease의 억제제인 phenylmethylsulfonil fluoride (PMSF)에 의해 활성이 억제되었으며, ATP를 첨가할 때 그 활성이 증가하여 ATP 의존성 효소임을 알 수 있었다. 위의 단백질 분해 효소를 부분 정제하기 위해 여러 chromatography를 실시하였는데, 먼저 DE52 (2.Sfx40 cm)에 통과시켰을 때, 0.05M-0.IM NaCl에 의해 유출되는 분획이 pH 6.0에서 황성을 나타내었으며, 0.25V- 0.3M에서 유출되는 분획이 pH 8.5에서 황성을 나타내었다. 이 분회들을 각각 Sephadex G-200 ($2.50{\phi}{\times}40cm$) 에 통과시켜 pH 6.0에서 활성을 나타내는 분획은 exclusion limit내에서, pH 8.5의 분획은 exclusion limit 외에서 분획을 얻었다. 이들을 각각 hydroxylapatite ($2.50{\phi}{\times}10cm$과 $2.5{\phi}{\times}20cm$)를 통과시켜 각각을 0.05M Phosphate로 유출되는 분회에서 높은 환성을 얻었다. 부분 정제된 분획들의 특성을 검토하기 위하여 억제제를 농도별로 처리하였을 때, pH 0.0에서의 분해 효소는 10-3M IAA에 의해 활성이 반감되어 cysteinyl acid protease임을 알 수 있었다. pH 8.5에서의 분해 효소는 10-5M PMSF에 의해 활성이 반감되었고, ATP에 의해 활성이 증가(ATP의 농도가 2.0mM 이상에서는 억제)하여 ATP-dependent neutral serine protease임을 알 수 있었다.

• BMB Reports
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• 제40권4호
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• pp.604-609
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• 2007

An Asp/His catalytic site of 10-formyltetrahydrofolate dehydrogenase (FDH) was suggested to have a similar catalytic topology with the Asp/His catalytic site of serine proteases. Many studies supported the hypothesis that serine protease inhibitors can bind and modulate the activity of serine proteases by binding to the catalytic site of serine proteases. To explore the possibility that soybean trypsin inhibitor (SBTI) can recognize catalytic sites of FDH and can make a stable complex, we carried out an SBTI-affinity column by using rat liver homogenate. Surprisingly, the Rat FDH molecule with two typical liver proteins, carbamoyl-phosphate synthetase 1 (CPS1) and betaine homocysteine S-methyltransferase (BHMT) were co-purified to homogeneity on SBTI-coupled Sepharose and Sephacryl S-200 followed by Superdex 200 FPLC columns. These three liver-specific proteins make a protein complex with 300 kDa molecular mass on the gel-filtration column chromatography in vitro. Immuno-precipitation experiments by using anti-FDH and anti-SBTI antibodies also supported the fact that FDH binds to SBTI in vitro and in vivo. These results demonstrate that the catalytic site of rat FDH has a similar structure with those of serine proteases. Also, the SBTI-affinity column will be useful for the purification of rat liver proteins such as FDH, CPS1 and BHMT.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.167-171
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• 2004

We constructed an oligo-d(T) primed directional cDNA library from the Bombyx mandarina whole larvae. In an effort to isolate genes expressed in the B. mandarina, 227 expressed sequence tags (ESTs) were generated by single-pass sequencing from the cDNA library. Sequence analysis showed that 107 clones (47.1%) were classified into known genes and 120 clones (52.9%) were novel transcripts, which are unknown for their function. Of the 107 known genes, the most abundant gene was found to be actin and followed by serine protease in the expression profile. Among these clones, a serine protease homolog (BmSP) which is a class of proteolytic enzymes isolated. Full-length sequence of the BmSP cDNA clone was 922 bp in length and has an open reading frame of 276 amino acids. The conserved histidine, aspatic acid and serine residues forming the catalytic center as well as cysteine residues contributing to three disulphide bonds also were found in Bmsp gene. mRNA expression analysis revealed a high and specific expression of the gene only in midgut tissue, suggesting that BmSP gene is closely associated with the expression of digestive enzyme.