• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.673-677
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• 1998

A inhibitor acting on substrate proteolytic enzyme was isolated from culture broth of Streptomyces sp. SK-862, which had been isolated from soil in Wonju City, by using the colloidal agar medium. The optimum culture temperature and initial pH for the production of the protease inhibitor was 28$^{\circ}C$ and pH 8.5, respectively. The optimum culture medium was composed of 1.5% glucose, 0.5% peptone, 0.1% K2PHO4, 0.05% CaCO3 and initial pH 8.5. The inhibitor production was maximum when the strain was incubated in shaking incubator at 70 strokes for 60 hours.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1688-1694
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• 2007

A gene encoding the mannanase of Bacillus subtilis WL-3, which had been isolated from Korean soybean paste, was cloned into Escherichia coli and the nucleotide sequence of a 2.7-kb DNA fragment containing the mannanase gene was subsequently determined. The mannanase gene, designated manA, consisted of 1,080 nucleotides encoding a polypeptide of 360 amino acid residues. The deduced amino acid sequence was highly homologous to those of mannanases belonging to glycosyl hydrolase family 26. The manA gene was strongly expressed in B. subtilis 168 by cloning the gene downstream of a strong B. subtilis promoter of plasmid $pJ27{\Delta}88U$. In flask cultures, the production of mannanase by recombinant B. subtilis 168 reached maximum levels of 300 units/ml and 450 units/ml in LB medium and LB medium containing 0.3% locust bean gum, respectively. Based on the zymogram ofthe mannanase, it was found that the mannanase produced by recombinant B. subtilis could be maintained stably without proteolytic degradation during the culture time.

• Current Research on Agriculture and Life Sciences
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• v.31 no.2
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• pp.108-112
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• 2013

Nuts are one of the most common sources of allergies in individuals of all ages. In order for a particular protein to render an allergic reaction, it must resist proteolytic digestion by intestinal enzymes. In this study, three well-known allergenic nuts, almonds, cashew nuts, and peanuts, were used as samples, and enzyme digestion with Bacillus protease and porcine pepsin was tested. A proteomic approach using two-dimensional gel electrophoresis and an MS/MS analysis was applied to visualize and identify the proteins that were resistant to enzyme digestion. Among the 150 protein spots tested, 42 proteins were assigned functions. Due to the lack of genomic databases, 41% of the identified proteins were grouped as hypothetical. However, 12% of them were well-known allergens, including AraH. The remainder were grouped as storage, enzymes, and binding proteins.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2437-2444
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• 2012

Tumor metastasis remains the principal cause of treatment failure and poor prognosis in patients with colorectal cancer. It is a multistage process which includes proteolysis, motility and migration of cells, proliferation in a new site, and neoangiogenesis. A crucial step in the process of intra- and extra-vasation is the activation of proteolytic enzymes capable of degrading the extracellular matrix (ECM). In this stage, urokinase plasminogen activator receptor (uPAR) and matrix metalloproteinases (MMPs) are necessary. Micrometastases need the presence of growth factor and vascular growth factor so that they can form macrometastasis. In addition, cell adhesion molecules (CAMs) and guanine nucleotide exchange factors (GEFs) play important roles in the progression of colorectal cancer and metastatic migration. Further elucidation of the mechanisms of how these molecules contribute will aid in the identification of diagnostic and prognostic markers as well as therapeutic targets for patients with colorectal metastasis.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.207-211
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• 1986

Lactic acid bacteria isolated from Kimchi were tested for inhibitory activity against E. coli, Streptococcus faecalis and Lactobacillus bulgaricus. The inhibitory strains appeared most frequently around the middle stage of fermentation during two weeks of observation, and the majority of them were identified as Pediococcus cerevisiae. The agent(s) responsible for the inhibitory activity of P. cerevisiae was inactivated by heat treatment at moderate temperature, but resistant to proteolytic enzymes. The production of the inhibitory compound(s) decreased when the pH of the medium was maintained at about 7 with phosphate buffer.

• Microbiology and Biotechnology Letters
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• v.25 no.4
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• pp.379-385
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• 1997

Several protease-deficient mutants of Aspergillus niger have been isolated by halo-screening on skim milk plate after UV irradiation of conidiospores. The extracellular proteolytic activities of the mutant strains grown in an optimized medium varied from 3% to 85% of that of the parental strain. Especially, two mutant strains named as ANPD-129 and ANPD-153, which had 3% and 49% of acid protease activity of the parental strain, respectively, were further characterized both physiologically and genetically. The growth rates of the mutants, ANPD-129 and ANPD-153, were similar to that of the parental strain, unlike other protease-deficient mutants. The diploid formed between the two mutants restored protease activity to a similar level of that of the parental strain. This result revealed that ANPD-129 and ANPD-153 had mutations at different loci. Using master strains with marked chromosomes these loci were assigned to linkage groups. The mutation locus (prt129) in ANPD-129 was assigned to linkage group VI and the locus (prt153) in ANPD-153 to linkage group III.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.404-409
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• 1999

The most favorable nitrogen source for the production of protease by Aspergillus oryzae PF was 2% soybean flour among sodium nitrate, ammonium sulfate, defatted soybean, skim milk, casein, peptone, and yeast extract. The production of protease from A. oryzae PF was higher at the concentration of 2% lactose than at variable concentration of glucose, sucrose, soluble starch, corn starch, potato starch, wheat starch, rice starch, cellulose, and gum arabic. Protease production was affected by the concentration of KH2PO4, Triton X-100, CaCo3, and MgSO4, and it was the highest at the highest at the concentration of 3% KH2PO4, 0.01% Triton X-100, 0.3% CaCO3, and 0.06% MGSO4.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.189-196
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• 1997

A producer of inhibitor against ${\beta}-glucosidase$ of Penicillium sp.-L4 was screened from Actinomycetes, and the isolated strain was identified as Streptomyces sp. The inhibitor produced was very stable against heat, acidic and alkaline conditions, proteolytic and amylolytic enzymes. The inhibotor was purified from culture broth through activated carbon treatment, ultrafiltration, anion and cation exchange, activated carbon columm, acetone precipitation and preparative HPLC. It showed inhibitory activities against a variety of dissacharide hydrolyzing enzymes produced by P.sp.-L4, and the mode of inhibition was competitive. Its structure and molecular formular was elucidated by IR, $^1H\;and\;^{13}C$ NMR and FAB/Mass spectrometry, which was identified as 1-deoxynojirimycin (dNM). dNM showed inhibitory effects on the cell growth and hydrolytic enzyme action of P.sp.-L4 on agar plate and infected lemon peel.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.2
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• pp.43-46
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• 2020

Huntington's disease (HD) is an inherited neurodegenerative disease caused by abnormal polyglutamine (polyQ) expansion in the huntingtin protein (Htt). There is no cure for HD so far. Although exact molecular mechanism of HD pathogenesis is still elusive, fibril formation of the expanded Htt is linked to the toxicity. In this study, we prepared the expanded Htt containing 46 glutamines, and induced the fibrillation by proteolytic cleavage. Fibrillation of the pathogenic Htt has been monitored by time course NMR experiment. The NMR-based monitoring method could be widely used to screen the candidates to inhibit the fibrillation of the pathogenic Htt.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.51-54
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• 1997

Lumbrokinase, potent fibrinolytic enzyme purified from earthworm, was immobilized onto the total artificial heart valves using photoreaction. This valve were implanted into the lamb for three days. After experiments, thrombus was observed in the untreated valves whereas no thrombus was observed in the lumbrokinase immobilized valves. The fibrinolytic activity and proteolytic activity of the implanted valve was examined. The fibrinolytic activity of the valve was remained after the implantation. The lumbrokinase could be a suitable fibrinolytic agents in the vascular contacting devices to reduce the thrombus.