• 한국식품영양학회지
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• 제15권4호
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• pp.364-369
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• 2002

방선균은 토양 속에 다양하게 존재하는 미생물의 일종으로 그람 양성 진정세균으로 이차대사산물을 생산하는 시기와 포자 착생이 시작되는 세포분화의 시기가 밀접한 관련이 있다. S. griseus는 streptomycin을 비롯한 다양한 종류의 endopeptidase 및 exopeptidase들을 생산한다. 방선균에서의 protease 생산은 많은 경우에 이차대사산물이 형성되거나 형태분화가 유도되는 시기에 동시에 시작된다는 점에서 Pretense가 이차대사물질 생산 및 세포분화에 일정한 기능을 수행할 것이 라는 점을 시사하고 있다. 본 연구에서는 S. griseus IFO 13350에서 클로닝한 SGPD protease가 각 strain에서 형태학적으로나 생리적으로 어떠한 gene dosage 효과를 미치는지 조사하는 것이었다. sprD 유전자가 S.lividans를 숙주로 사용한 시스템에서 대량발현이 성공적으로 되는 것을 확인한 후, 본 유전자를 클로닝한 S. griseus IFO13350 균주와 이의 A-factor 결손주인 S. griseus HH1에 형질전환하였다. S. griseus HH1과 S. griseus IFO13350에서는 protease activity가 벡터만 도입된 대조군과 sprD 유전자가 들어간 형질전환체에서 큰 차이를 보이지 않았다. 또한 S. griseus IFO 13350 및 HH1 모두에서 생리학적·형태학적 분화의 차이를 발견하지 못하였다. Chymotrypsin계열의 pretense를 암호화하는 유전자만이 S. griseus에서 발현이 repression된다는 사실을 본 연구 결과를 통하여 알게 되었다. 이를 바탕으로 sprD유전자와 동일계열의 chymotrypsin 계열의 유전자들이 공통적으로 S. griseus에서 repression 되는 일반적인 기전이 있을 것으로 판단, chymotrypsin계열 유전자들의 promoter부분의 염기 상동성을 조사하였다 번역개시부위 바로 상부 유전자부터 상동성을 조사한 결과 적어도 상당부분의 염기배열이 잘 보존된 지역이 존재함을 알게 되었다. 향후 이들 발현기구의 조절기구를 연구함으로서 protease의 기능을 밝히는데 좋은 단서를 제공할 것으로 판단된다.

• Mycobiology
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• 제30권3호
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• pp.154-159
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• 2002

Fifty cases of dermatomycoses were recorded from adult male and female at Qena Gvernorates. These included tinea capitis(62% of total cases), tinea corporis(20%), tinea versicolor(12%) and tinea unguium(6%). Males are more susceptible to all cases of tinea than females. Thirty-one species and 2 varieties belonging to 16 genera were recovered from several infection sites. These were identified as Aphanoascus fulvescens, A. terreus, Arthroderma fulva, A. obtusa, Trichophyton rubrum and T. soudanense. Several saprophytes were also found. These were : Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Cochliobolus lunatus, Mycosphaerella tassiana, Penicillium chrysogenum and P. citrinum. Twenty-one isolates were able to hydrolyze gelatin with variable capabilities. T. rubrum was the most active protease producer. The maximum production of protease was obtained at 8 days of incubation at $30^{\circ}C$ in Sabouraud's basal medium with maltose as a carbon source and pepton as a nitrogen source. The optinal pH for the maximum production of protease was pH 6.

• Journal of Life Science
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• 제11권1호
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• pp.42-46
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• 2001

Subtilisin YaB, produced by alkalophilic Bacillus strain YaB, is an extracellular alkaline serine protease having 55% homology to subtilisin BPN'. It is synthesized as a 378-amino acid preproenzyme and secreted into the culture medium as a 265-amino acid mature protease. To examine the role of pro-sequence for the secretion of subtilisin YaB, we have studied the expression, in Bacillus subtilis, of a mutant preprosubtilisin YaB in which active site Ser214 is substituted with Cys. The use of a six protease-deficient strain, WB600, was required for its efficient production. The prosubtilisin YaB, thus produced, was indeed secreted into the culture medium and was processed to its mature form upon treatment with exogenously added active subtilisin YaB. From these results, we have concluded that the processing of pro-sequence is not essential for the secretion of the enzyme.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.621-626
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• 1994

Cysteine showed strong inhibitory effect on growth and protease production of Pseudo- monas sp. RP-222 and its mutant, MR-3966. Mid- to late-log phase cells were most sensitive to the presence of 10 mM cysteine. The inhibition caused by cysteine was almost completely overcome by addition of isoleucine, leucine and valine mixture to the medium, and inclusion of iso#leucine alone could greatly reduce the inhibitory effects of cysteine. Homocysteine and #cysteine, sulfur compounds having similar structure as cysteine, inhibited to varying degrees the growth of both strains. Cysteine and homocysteine were strong inhibitors of threonine deaminase but not transa#- minase B. These results suggest a relationship between the growth-inhibitory effects of cysteine and other sulfur compounds and the inhibition of isoleucine synthesis at the level of threonine deaminase.

• 한국식품영양과학회지
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• 제20권4호
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• pp.388-394
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• 1991

Alkaline protease producing bacteria were isolated from soil and identified as Bacillus sp. CW-1121. It was found that the production of alkaline protease reached to maximum in 5 day of fermentation at 4$0^{\circ}C$. The enzyme was purified by ammonium sulfate precipitation, gel filtration on Sephadex G-150 and DEAE-cellulose ion-exchange chromatography. The homogeneity of the purified enzyme was verified by polyacrylamide gel electrophoresis. The enzyme was purified 5.72 fold and yield of the enzyme purification was 16.71%. When the purified enzyme was applied to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the molecular weight was estimated to be 55, 000.

• 한국환경농학회지
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• 제35권4호
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• pp.294-301
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• 2016

BACKGROUND: Recent studies have described the importance of microbes and enzymes that can compost food waste. This study was carried out to improve production of protease of isolated microbes from food waste. METHODS AND RESULTS: Seven bacteria isolated from various sources were screened for protease production by adding skim milk into the agar medium. About 7 microbes producing protease were tested, and strain JH-35 showed the highest protease activity among them. The strain was identified as Bacillus amyloliquefaciens JH-35 based on morphological, cultural, physiological characteristics and 16S rRNA. In the fermentation experiment, the assay B. amyloliquefaciens JH-35 showed the highest protease activity in the condition of 1% glucose, 1.5% yeast extract and 0.2%$ K_2HPO_4$. The optimal condition of culture with temperature $35^{\circ}C$, initial pH of 7 and shaking speed of 200 rpm and 24 hr. CONCLUSION: The protease of the B. amyloliquefaciens JH-35 had its activity at pH 7 and the optimal culture time was 24 hr. Also, B. amyloliquefaciens JH-35 was high salt tolerance. Our results suggest that B. amyloliquefaciens JH-35 from food waste may have the potential to degrade protein and carbohydrate in food waste.

• 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.

• Journal of Microbiology and Biotechnology
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• 제33권2호
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• pp.195-202
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• 2023

Protease is a widely used enzyme particularly in the detergent industry. In this research, we aimed to isolate alkaline protease-producing bacteria for characterization as a laundry detergent additive. The screening of alkaline protease production was investigated on basal medium agar plus 1% skim milk at pH 11, with incubation at 30℃. The highest alkaline protease-producing bacterium was 6BS15-4 strain, identified as Bacillus gibsonii by 16S rRNA gene sequencing. While the optimum pH was 12.0, the strain was stable at pH range 7.0-12.0 when incubated at 45℃ for 60 min. The alkaline protease produced by B. gibsonii 6BS15-4 using dairy effluent was characterized. The optimum temperature was 60℃ and the enzyme was stable at 55℃ when incubated at pH 11.0 for 60 min. Metal ions K⁺, Mg²⁺, Cu²⁺, Na⁺, and Zn²⁺ exhibited a slightly stimulatory effect on enzyme activity. The enzyme retained over 80% of its activity in the presence of Ca²⁺, Ba²⁺, and Mn²⁺. Thiol reagent and ethylenediaminetetraacetic acid did not inhibit the enzyme activity, whereas phenylmethylsulfonyl fluoride significantly inhibited the protease activity. The alkaline protease from B. gibsonii 6BS15-4 demonstrated efficiency in blood stain removal and could therefore be used as a detergent additive, with potential for various other industrial applications.

• 한국식품저장유통학회지
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• 제17권3호
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• pp.410-417
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• 2010

우리나라 전통발효식품의 하나인 청국장으로부터 고 비활성 세포외 protease 생산능이 우수한 균주를 분리하고 그 특성을 조사하였다. 분리된 균주 중 D14 균주 배양 상징액의 protease 활성이 15.2 U/mL로서 가장 강하였으며 비활성 또한 40.0 U/mg protein으로서 가장 강하게 나타났다. 이 균주의 특성을 조사한 후 Berge's Manual of Systematic Bacteriology에 준하여 Bacillus subtilis로 동정하였다. 균주 D14의 16S rDNA 염기서열을 분석하여 B. subtilis subsp. subtilis NCIB 3610 균주와 99.9%의 상동성을 가짐을 확인 하였다. 또한 16S rDNA의 염기서열을 토대로 계통분석을 통하여 다른 Bacillus sp.의 균주들보다 NCIB 3610 균주와 유전적으로 매우 가까운 관계에 있음을 확인하였다. Soluble starch는 사용한 탄소원 중 가장 높은 수준의 protease 생산능을 보였으나 단당류, 이당류 등은 모두 효소 생산능에 대하여 저해효과를 나타내었다. 특히 fructose를 첨가한 경우에는 12.7%, glucose를 첨가한 경우에는 35.9% 수준의 효소 생산능을 나타내었다. 질소원의 경우는 soytone의 첨가구에서 대조구에 비하여 약 61.4% 수준의 효소활성을 나타내어 저해효과가 가장 높았으며 다른 질소원은 효소 생산에 크게 영향을 미치지 않았다.

• 한국미생물·생명공학회지
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• 제21권5호
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• pp.468-472
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• 1993

For the production of Casein Phosphopeptide(CPP) inhibiting the insolubility of calcium, 10% sodium caseinate was treated with 1.5% of protease from Streptococcus sp.. Optimal conditions and productivity for the CPP production, and properties of the CPP were compared with tryptic hydrolysates of sodium caseinate. Optimum conditions of pH, temperature and reaction time were 8.0, 50C, 4 hrs, respectively. Under these conditions the productivity of CPP was 23% and Molecular weight of CPP was ranged from 3, 000 to 17, 000. The results also showed that the insolubility of calcium was completely inhibited by using 1.5 times of CPP for the amount of calcium.