• Parasites, Hosts and Diseases
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• v.32 no.4
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• pp.231-242
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• 1994

Pnragonimus westermnni, the lung fluke, is known to migrate to the pulmonary tissue of mammalian hosts and causes pathological changes in the lungs. An acidic thiol-dependent proteinase with a molecular weight of approximately 20,000 daltons was purified to homogeneity using ion-exchange chromatography and gel filtration chromatography. On SDS-PAGE, the molecular weight of the enzyme was 17,500 daltons. Isoelectric point was 6.45. The enzyme was similar to the acidic cysteine proteinase of vertebrates in the properties of pH optimum, substrate specificity and inhibitor sensitivity. Enzymatic activity was stable at pH 5.5 for at least two days when stored at 4℃. The cysteine proteinase was capable of degrading collagen and hemoglobin. Sera of patients with paragonimiasis and mice infected with R westermani reacted in immunoblots with the partially purified proteinase. This result suggested that the cysteine proteinase of P. westermnni may play a role in migration in tissues, and in acquisition of nutrients by parasites from the host. It is also potentially an antigen for the serodiagnosis of paragonimiasis.

• Tuberculosis and Respiratory Diseases
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• v.56 no.3
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• pp.289-296
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• 2004

Background : Mucus hypersecretion in the patients with airway diseases represents poor prognosis as well as discomfort. However, there is no known therapy for its effective control. One important component of mucus is mucin, a glycosylated protein, which endows mucus with viscosity. We studied whether a proteinase has a role in mucin secretion and if so, which. Methods : (1) Inhibition of mucin secretion Group-specific proteinase inhibitors were tested to evaluate whether a proteinase belonging to a group of proteinases plays a role in mucin secretion. Phenylmethylsulfonyl fluoride(PMSF, a serine proteinase inhibitor), E-64(a cysteine proteinase inhibitor), Pepstatin(an aspartic proteinase inhibitor) and 1, 10-Phenanthroline(a metalloproteinase inhibitor) were treated into the Calu-3 cell line for 24 hours. The enzyme linked immunoabsorbant assay(ELISA) for MUC5AC was performed to evaluate the amount of mucin secretion and to compare with a control. (2) Stimulation of mucin secretion Matrix metalloproteinase-9(MMP-9), MMP-12 and TACE(TNF-alpha converting enzyme), which are known to be related with airway diseases, were used to be treated into Calu-3 for 24 hours. ELISA for MUC5AC was performed to evaluate the amount of mucin secretion and to compare with the controls. Results : (1) PMSF($10^{-4}M$), E-64($10^{-4}M$), Pepstatin($10^{-6}M$) and 1, 10-Phenanthroline($10^{-4}M$) reduced the MUC5AC secretion by $1{\pm}4.9%$(mean${\pm}$standard deviation; P=1.0 compared with the control), $-6{\pm}3.9%$(P=0.34), $-13{\pm}9.7%$(P=0.34) and $41{\pm}8.2%$(P=0.03), respectively. (2) The amounts of MUC5AC secretion stimulated by MMP-9(250ng/ml), MMP-12(100ng/ml) and TACE(200ng/ml) were $103{\pm}6%$(P=0.39), $102{\pm}8%$(P=1.0) and $107{\pm}13%$(P=0.39), respectively, compared with the controls. Conclusion : Metalloproteinase(s) is (are) suggested to play a role in mucin secretion. It appears that metalloproteinases, other than MMP-9, MMP-12 or TACE, affect the mucin secretion in this in vitro model.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.204.1-204
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• 1996

No Abstract, See Full Text

• Journal of Microbiology
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• v.35 no.2
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• pp.109-116
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• 1997

An extracellular proteinase of Candida albicans was purified by a combination of 0~75% ammonium sulfate precipitation, DEAE Sepharose Fast Flow ion exchange chromatography, and Sephacryl S-200 HR molecular sieve chromatography. Its mlecular weight was approximately 41 kDa on SDS-PAGE and isoelectric point was 4.4. The enzyme was inhibited by pepstain A. Optimum enzyme activity ranged from pH 2.0 to 3.5 with its maximum at pH 2.5 and a temperature of 45$^{\circ}C$. The addition of divalent cations, $Ca^{2+}$, Zn$^{2+}$ and $Mg^{2+}$, resulted in no significant inhibition of enzymatic activity. However, some inhibitory effects were observed by Fe$^{2+}$, Ag$^{2+}$ and Cu$^{2+}$. With BSA as substrate, an apparent $K_m$ was determined to be 7$\times$10$^{-7}$ M and $K_i$, using pepstatin A as an inhibitor, was 8.05$\times$10$^{-8}$ M. N-terminal amino acid sequence was QAVPVTLXNEQ. Degradation of BSA and fibronectin was shown but not collagen, hemoglobin, immunoglobulin G, or lysozyme. The enzyme preferred peptides with Glu and Leu at the P$_1$ position, but the enzyme activity was highly reduced when the P$_2$ position was phe or pro. This enzyme showed antigenicity against sera of patients with candidiasis.

• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.261-268
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• 1998

The present study was undertaken to investigate the role of cysteine proteinase of Trichomonas vaginalis in escaping from host defense mechanism. A cysteine proteinase of T. vaginalis was purified by affinity chromatography and gel filtration. Optimum pH for the purified proteinase activity was 6.0. The proteinase was inhibited by cysteine and serine proteinase inhibitors such as E-64, NEM, IAA, leupeptin. TPCK and TLCK, and also by $Hg^{2+}$, but not affected by serine-, metallo-, and aspartic proteinase inhibitors such as PMSF, EDTA and pepstatin A. However, it was activated by the cysteine proteinase activator, DTT. The molecular weight of a purified proteinase was 62 kDa on gel filtration and 60 kDa on SDS-PAGE. Interestingly, the purified proteinase was able to degrade serum IgA, secretory IgA, and serum IgG in time- and dose-dependent manners. In addition, the enzyme also degraded hemoglobin in a dose-dependent manner. These results suggest that the acidic cysteine proteinase of T. vaginalis may play a dual role for parasite survival in conferring escape from host humoral defense by degradation of immunoglobulins, and in supplying nutrients to parasites by degradation of hemoglobin.

• BMB Reports
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• v.28 no.1
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• pp.68-71
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• 1995

Bovine gastricsin catalyzes peptide synthesis over an optimum range of pH 4~5, resulting in satisfactory yields of methyl esters and p-nitroanilides of benzyloxycarbonyl tetra- to hexa-peptides, provided that hydrophobic amino acid residues form new peptide bonds. The effectiveness of the enzyme also depends on the nature of adjacent amino acid residues. An aspartic proteinase with a characteristic gastricsin specificity pattern would be useful for the synthesis of middle-length peptides.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.204.2-204
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• 1996

No Abstract, See Full Text

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.148-149
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• 2001

Protein inhibitors are proteins or peptides capable of inhibiting catalytic activities of proteolytic enzymes. They are grouped primarily as either serine, cysteine, aspartic or metallto-proteinase inhibitors. Pretense inhibitors have been hewn since the end of the last century in nematodes and human blood serum, and their ubiquitous distribution in microorganisms, animals and plants has been widely documented. (omitted)

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.28-35
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• 1998

An antimicrobial peptide producing bacterium, Bacillus subtilis A405, was screened and identified among 700 of antagonistic bacteria. The heat-resistant antimicrobial peptide, AMP-405, was purified from the broth culture of B. subtilis A405 through $20{\sim}40%$ ammonium sulfate precipitation and ultrafiltration. The AMP-405 exhibited strong antimicrobial activities against Botrytis cinerea, Cercospora sp., Fusarium oxysporum, Penicillium digitatum, Celletotrichum gloeosporioides, Rhizoctonia solani, Pythium ultimum, Pyricularia oryzae, Escherichia coli, Pseudomonas spp. and Candida albicans. The molecular weight of the peptide was about 3.0 kDa determined by SDS-PAGE, Native-PAGE and Tris-Tricine gradient electrophoresis, and composed of 9 kinds of amino acid such as aspartic acid, glycine, serine, glutamine, valine, leucine, isoleucine, proline, tyrocine. To determine the efficiency of AMP-405 as a potential maintenance of fruits freshness, cherry tomato was srored at $25^{\circ}C$ for 2 weeks after treatment with $50{\mu}g/ml$ of AMP-405 and $10^{5}$ spores/ml of Botrytis cinerea simultaneously. Treatment with AMP-405 resulted in significantly less infection by Botrytis cinerea, than the treatment with tap water as a control.

• Applied Biological Chemistry
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• v.37 no.2
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• pp.65-71
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• 1994

Chungkook-Jang was produced by fermenting Bacillus licheniformis CN-115. The changes of chemical composition, enzyme activity, and amino acids during the fermentation were investigated. The proximate composition was shown irregular fluctuation phenomenon during the fermentation, but only the moisture tended some reducing during the fermentation just after steaming. The content of amino nitrogen was increased radically after the 36 hours of fermentation and became the highest level at 18.072 mg/g at the 60 hours of it. In accordance with the fermentation of Chungkook-Jang, pH got to the 8.39 at 60 hours with increasing, protease activity was increased according to the fermentation and acid and neutral protease activity was reduced after being reached at the highest activity at 48 hours. The most suitable pH was 6.5 and temperature was $35^{\circ}C$ for dissolution-activated of protein in the process of fermentation of Chungkook-Jang. The content of water soluble protein and the content of salt soluble protein were increased at continuously according to the fermentation time of Chungkook-Jang the largest quantity. The molecular weight of water soluble protein of Chungkook-Jang fermented for 48 hours was about 19,000. The amino acids of water soluble protein just after steaming were totally 16 kinds and proline was amino acid and them was in series by glutamic acid and serine in that ordered. The amino acids salt soluble protein, just after steaming were totally 16 kinds and was the largest quantity phenylalanine, glutamic acid and aspartic acid and aspartic acid in that order.