• Journal of Plant Biotechnology
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• 제37권3호
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• pp.327-336
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• 2010

Cysteine proteases have been known as a critical factor in plant defense mechanisms in pineapple, papaya, or wild fig. Papain or ficin is one kind of cysteine proteases that shows toxic effects to herbivorous insects and pathogenic bacteria. However, resistance to bacterial soft rot of plants genetically engineered with cysteine protease has been little examined thus far. We cloned a cysteine protease cDNA from Ananas comosus and introduced the gene into Chinese cabbage (Brassica rapa) under the control of the cauliflower mosaic virus 35S promoter. The transgene was stably integrated and actively transcribed in transgenic plants. In comparisons with wild-type plants, the $T_2$ and $T_3$ transgenic plants exhibited a significant increase in endo-protease activity in leaves and enhanced resistance to bacterial soft rot. A cDNA microarray analysis revealed that several genes were more abundantly transcribed in the transgenic than in the wild type. These genes encode a glyoxal oxidase, PR-1 protein, PDF1, protein kinase, LTP protein, UBA protein and protease inhibitor. These results suggest an important role for cysteine protease as a signaling regulator in biotic stress signaling pathways, leading to the build-up of defense mechanism to pathogenic bacteria in plants.

• 미생물학회지
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• 제30권6호
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• pp.507-513
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• 1992

Serratia marecescens RH1 isolated from soil samples produced large amount of extracellular proteases. One of the genes encoding an extracellular protease form S. marcescens RH1 was cloned in Escherichia coli by shot gun cloning method. The cloned protease, SSP, was stably expressed by its own promoter and excreted into the extracellular medium from E. coli host (ORF) of 3.135 nucleotides corresponding to 1.045 amino acids (112 kDa). The nucleotide and deduced amino acid sequence of SSP showed high overall homology (88%) to one of the S. marcescens protease (27), but low homology to other serine protease families. The optimal pH and temperature of the enzyme were pH 9.0 and 45.deg.C respectively. The activity of protease was inhibited by phenylmethylsulfonyl fluoride (PMSF), which suggests that the enzyme is a serine protease.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.410-416
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• 2008

The gene SfXyn10, which encodes a protease-resistant xylanase, was isolated using colony PCR screening from a genomic library of a feather-degrading bacterial strain Streptomyces fradiae var. k11. The full-length gene consists of 1,437bp and encodes 479 amino acids, which includes 41 residues of a putative signal peptide at its N terminus. The amino acid sequence shares the highest similarity (80%) to the endo-1,4-${\beta}$-xylanase from Streptomyces coelicolor A3, which belongs to the glycoside hydrolase family 10. The gene fragment encoding the mature xylanase was expressed in Escherichia coli BL21 (DE3). The recombinant protein was purified to homogeneity by acetone precipitation and anion-exchange chromatography, and subsequently characterized. The optimal pH and temperature for the purified recombinant enzyme were 7.8 and $60^{\circ}C$, respectively. The enzyme showed stability over a pH range of 4.0-10.0. The kinetic values on oat spelt xylan and birchwood xylan substrates were also determined. The enzyme activity was enhanced by $Fe^{2+}$ and strongly inhibited by $Hg^{2+}$ and SDS. The enzyme also showed resistance to neutral and alkaline proteases. Therefore, these characteristics suggest that SfXyn10 could be an important candidate for protease-resistant mechanistic research and has potential applications in the food industry, cotton scouring, and improving animal nutrition.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.761-768
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• 2007

Serratia proteamaculans HY-3 isolated from the digestive tract of a spider produces an extracellular protease named arazyme, with an estimated molecular mass of 51.5 kDa. The purified enzyme was characterized as having high activities at wide pH and temperature ranges. We further characterized biochemical features of the enzymatic reactions under various reaction conditions. The protease efficiently hydrolyzed a broad range of protein substrates including albumin, keratin, and collagen. The dependence of enzymatic activities on the presence of metal ions such as calcium and zinc indicated that the enzyme is a metalloprotease, together with the previous observation that the proteolytic activity of the enzyme was not inhibited by aspartate, cysteine, or serine protease inhibitors, but strongly inhibited by 1,10-phenanthroline and EDTA. The araA gene encoding the exoprotease was isolated as a 5.6 kb BamHI fragment after PCR amplification using degenerate primers and subsequent Southern hybridization. The nucleotide sequence revealed that the deduced amino acid sequences shared extensive similarity with those of the serralysin family of metalloproteases from other enteric bacteria. A gene(inh) encoding a putative protease inhibitor was also identified immediately adjacent to the araA structural gene.

• 미생물학회지
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• 제47권3호
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• pp.194-199
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• 2011

알칼리성 protease를 생산하는 호알칼리성 균주를 분리하여 Bacillus pseudofirmus HS-54로 동정하였고, HS-54가 생산하는 알칼리성 protease를 ammonium sulfate 침전, DEAE cellulose chromatography, sephadex G-100 gel filtration을 통과시켜 정제하였는데, 정제된 protease의 분자량은 27 kDa이었다. 정제된 효소의 반응최적 pH는 10.0이었고 pH 7.0-11.0에서 비교적 안정하였다. 또한 정제된 효소의 반응최적 온도는 $50^{\circ}C$이었고 $10-55^{\circ}C$에서 안정하였다. 금속이온에 대한 영향은 $Ca^{2+}$와 $Mg^{2+}$ 등에 의해 효소활성이 촉진되었으나, $Hg^{2+}$, $Zn^{2+}$, $Cu^{2+}$, $Al^{3+}$ 등에 의해서 효소활성이 저해되었다. 본 효소는 PMSF에 의해 강하게 저해를 받는 것으로 보아 serine protease에 속하는 것으로 판단된다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 1998년도 제38회 춘계학술발표대회
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• pp.54.2-54.2
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• 1998

• Journal of Plant Biotechnology
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• 제33권1호
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• pp.27-32
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• 2006

파인애플 (Ananas comosus) 줄기에서 얻어지는 bromelain은 단백질 분해효소 중 cysteine protease의 복합체로 알려져 있다. 본 연구에서는 제주산 파인애플 줄기를 이용하여 bromelain 관련 유전자를 분리하였다. 분리된 BL1 유전자는 총 933개의 염기서열로 311개의 아미노산을 coding 하였다. 지금 까지 알려진 식물 유래 bromelain 관련 유전자와의 alignment 분석한 결과 BAA21929 유전자와 94%, T10516 유전자와 93% 및 P14518 유전자와 81%의 상동성을 보였다. BL1 유전자를 상추 게놈내에 도입하고자 NPTII 유전자 와 BL1 유전자로 제작한 pBI 121 BL 벡터를 Agrobacterium tumefacience LBA4404에 도입한 후, 상추잎 절편에 감염시켜 embryogenic callus 및 재분화 식물체를 육성하였다. 이들식물체로부터 T1세대를 육성하여 PCR 분석을 통해 왜래유전자의 도입 여부를 확인하였다. 또한 형질전환체의 발현여부는 Nothern blot분석 및 eno protease활성을 통해 형질전환체에서 BL1유전자가 안정적으로 상추세포내에서 발현되고 있음을 확인하였다. 따라서 본 실험에서 육성된 bromelain 관련 BL1 유전자가 도입한 형질전환 상추를 육종소재르 활용한다면 상업적으로 유용한 단백질을 분해하는 가수분해효소로써 건강 보조제, 사료첨가제 등에 널리 사용할 수 있을 것으로 생각되어진다.

• 한국미생물·생명공학회지
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• 제26권5호
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• pp.450-455
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• 1998

Alkaline protease를 대량생산하는 Aspergillus oryzae를 만들기 위하여 A. oryzae의 alkaline pretense 유전자 alpA를 고발현시키는 plasmid pTAalp를 제조하고 이 plasmid로 A. oryzae M-2-3 균주를 형질전환시켰다. 16개의 형질전환체를 얻어 이들의 protease생산성을 skim milk 분해에 의한 halo 형성능에 의하여 확인하였다. 또한 protease 생산성이 증가한 형질전환체는 pTAalp가 multi-copy로 염색체 안에 integration되어 있음을 Southern blot에 의하여 확인하였고, 이들의 배양액을 polyacrylamide gel전기영동에 의하여 분석한 결과, 형질전환체 No. 14에서는 전체 분비단백질의 80-90%가 alkaline protease 임을 알 수 있었다. 간장원료 분해실험의 결과 No. 14에 의한 원료분해액은 간장 양조용 대조균에 의한 분해액보다 TN이 증가하였으며 원료분해율도 1.4-1.5배로 증가되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권12호
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• pp.1769-1774
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• 2001

Bacillus licheniformis strains L-25 and PWD-1 are two thermophilic feather-degrading bacteria. Despite isolated from different environmental conditions, they were both capable of breaking down chicken feathers and growing in a medium in which feather was the only source of carbon and nitrogen. A 1.46-kb keratinase gene (ker B) was isolated from strain L-25 by a polymerase chain reaction (PCR) using L-25 genomic DNA as templates. Sequencing results reveal that ker B shares great sequence identity with a previously published keratinase gene of B. licheniformis PWD-1 (ker A). Only two amino acids differences were found in the deduced amino acid sequence between the keratinases from L-25 and PWD-1. However several nucleotide changes were found upstream of the putative promoter region. Protease inhibition studies indicated that neutral protease activity accounted for approximate 25 to 30% of total extracellular proteolytic activity produced by strain L-25 in the feather medium. In contrast, no measurable neutral protease activity was produced by strain PWD-1 in the feather medium. When glucose (1%), a common catabolic repressor, was added into the feather medium, L-25 was still able to grow and produce keratinase. Strain PWD-1 produced no neutral protease activity and its growth was severely inhibited in the feather medium containing glucose. L-25 produced an enhanced level of keratinase in the feather medium in comparison with PWD-1.

• International Journal of Industrial Entomology and Biomaterials
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• 제25권2호
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• pp.181-185
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• 2012

Chymotrypsin serine protease is one of the main digestive proteases in the midgut of and is involved in various essential processes. In a previous study, a gene encoding a chymotrypsin-like protease, Hi-SP1, was cloned from the larvae of Hermetia illucens and characterized. In this study, we produced the recombinant chymotrypsin-like protease Hi-SP1 in Escherichia coli cells. The molecular weight of the recombinant Hi-SP1 was estimated to be approximately 26 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western-blotting. Chymotrypsin activity was detected when AAPF was used as the substrate. Examination of the effects of temperature and pH revealed that the proteolytic activity of recombinant Hi-SP1 decreased markedly at temperatures above $30^{\circ}C$, and the optimum pH was found to be 10.0.