• Parasites, Hosts and Diseases
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• v.37 no.1
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• pp.39-46
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• 1999

As a preliminary study for the explanation of pathobiology of Neodiplostomum seoulense infection. a 54 kDa protease was purified from the crude extract of adult worms by sequential chromatographic methods. The crude extract was subjected to DEAE-Sepharose Fast Flow column, and protein was eluted using 25 mM Tris-HC1 (pH 7.4) containing 0.05. 0.1, 0.2 and 0.4 M NaC1 in stepwise elution. The 0.2 M NaCl fraction was further purified by Q-Sepharose chromatography and protein was eluted using 20 mM sodium acetate (pH 6.4) containing 0.05, 0.1. 0.2 and 0.3 M NaCl, respectively. The 0.1M NaCl fraction showed a single protein band on SDS-PAGE carried out on a 7.5-15% gradient gel. The proteolytic activities of the purified enzyme were specifically inhibited by L-trans-epoxy-succinylleucylamide (4-guanidino) butane (E-64) and iodoacetic acid. The enzyme, cysteine protease. showed the maximum proteolytic activity at pH 6.0 in 0.1 M buffer, and degraded extracellular matrix proteins such as collagen and fibronectin with different activities. It is suggested that the cysteine protease may playa role in the nutrient uptake of N. seoulense from the host intestine.

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.230-234
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• 2003

An extracellular protease of Bacillus amyloliquefaciens S94 was purified to apparent homogeneity. The enzyme activity was strongly inhibited by general inhibitor for serine protease, PMSF, suggesting that the enzyme is a serine protease. The purified enzyme activity was inhibited by leucine peptidase inhibitor, bestatin, suggesting that the enzyme is a leucine endopeptidase. When the enzyme was chemically modified with PMSF, which specifically reacted with serine residue on the enzyme, the activity was eliminated. The endopeptidase activity was inhibited by the modifier which chemically modified carboxyl group of aspartate and glutamate. PLP, which would modify lysine residue, did not affect the endopepetidase activity to a greater extent. This demonstrates that serine and aspartate (or glutamate) residues of enzyme would participate in a important function of the endopeptidase activity.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.379-387
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• 2003

The freeze dried young antler was extracted by water and proteases. In case of water extraction, the extraction rate was highest when it was reacted in 5% of concentration for 6 hours at 50$^{\circ}C$. The result of HPLC analysis of extract shows that high molecular peak in water extract was transformed into low molecular polk by proteases. The rate of low molecular peak was highest when bacteria protease was used, and its second highest rate was pepsin, but the effect of papain on it was low, The extraction rate of young antler reacted for 5 hours was 33.4%(absorbance 13.25 at 280nm) of bacteria protease, 22.4%(absorbance 10.06) of papain, and 30.2% (absorbance 11.34) of pepsin. The young antler was boiled for 30min and it was reacted by proteases for 5 hours at 50$^{\circ}C$. The extraction rate of it was 47,6%(absorbance 12,54) of bacteria protease, and 26,4%(absorbance 7,48) of papain, and 45.6%(absorbance 7.23) of pepsin, In protein content, water extract was 52,1%, bacteria protease extract was 37.8%, and in amino acid content, water extract was 16.3%, bacteria protease extract was 31.96%, in ash content, water extract was 8.8%, bacteria protease extract was 5.6% by dry base. In mineral content, water extract contains 3.6% of Ca, 8.6% of P, 0.01% of Mg, 1.4 % of Na, 0.02 % of F, and bacteria protease extract contains 2.5% of Ca, 11.8% of P, 0.046 % of Mg, 2.1 % of Na, 0.018 % of F by dry base.

• Journal of Plant Biotechnology
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• v.31 no.4
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• pp.319-323
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• 2004

Soluble latex protein fraction excreted from Euporbia lathyris laticifer was resolved by 10% SDS-polyacrylamide gel electrophoresis to identify distinctively displayed latex major protein bands including ELp65, ELp55, ELp43, ELp32 and ELp23. Among them, ELp65 was purified by ammonium sulfate precipitation, gel permeation chromatography and ion exchange chromatography. Its N-terminal amino acid sequencing revealed its homology to the leading region of mature peptide of tomato p69a subtilisin-like protease, suggesting a certain role involved in plant defense system. In the analysis of Southern blot hybridization using PCR-amplified tomato p69a probe DNA, E. lathyris genome was suggested to have a gene family consisting of 3-5 gene members putatively encoding subtilisin-like proteases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.461-467
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• 2009

A bacterial strain was screened and identified from sea sediments in Tongyeong coastal area in order to obtain proteases or peptidase cleaving C-terminal of glutamic acid. Strain TS0611, which showed the highest activity from 5 isolated protease producing strains, was selected and its properties investigated. Strain TS0611 was a gram-positive rod, $1.2\;{\mu}m$ in cell length, catalase positive, motility-positive, melanin-negative and grew at 15~$50^{\circ}C$, and hydrolyzed gelatin and casein. This strain was identified as Bacillus thuringiensis or Bacillus cereus based on results from the API system(API 50 CHB) which examined saccharides properties, fatty acid composition of cell wall, and 16S rRNA gene sequence.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.68-73
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• 2016

Lactic acid bacteria showing both protease activity and the capacity to produce casein phosphopeptide (CPP) were isolated from Korean kimchi, a traditional food made from fermented vegetables. Among the 450 strains of isolated lactic acid bacteria, the strain MG-379 showed high protease activity and the highest ability to produce CPP. Characterization results showed that MG-379 was gram-positive and measured $0.6-0.8{\mu}m$ in diameter. DNA sequencing of MG-379 and comparison with other sequences using BLAST revealed a 100% identity with the sequence of Enterococcus faecalis. However, MG-379 showed a higher CPP-producing ability than E. faecalis KCCM 40450. Accordingly, MG-379 was newly named as E. faecalis MG-379. Amount of free calcium liberated by CPPs was 2227.5 and 1151.6 mg/kg for E. faecalis MG-379 and E. faecalis KCCM (control), respectively.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.160-165
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• 1996

An alkalophilic bacterium producing alkaline protease(s) was isolated from soil. It was a Gram-positive, non-sporulating, immotile, irregular rod, strictly aerobic, and weak acid-forming bacterium. The morphological, physiological, and biochemical characteristics of the isolate resembled those of the Coryneform bacteria. However, there was not any species within this genera to which this microorganism can be closely matched. Therefore, it is provisionally identified as a Coryneform bacterium TU-19.

• YAKHAK HOEJI
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• v.2 no.1_2
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• pp.41-47
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• 1953

"Kimchi" is a most popular pickled Vegetables in Korea. In this paper, eight strains of gram positive rocls and two strains of gram positive cocci are isolated from "Kimchi". For the each isolated strains, the acid production test against carbohydrate and production test of amylase, protease, esterase, and general biological tests are investigated. The most active one for the amylase production is No.2 strain the most active one for the Protease production is No.5,6, and 9 strains. And that for Esterase production is No.9 strain (see the original paper on the results in this journal page)

• Journal of Life Science
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• v.21 no.2
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• pp.309-315
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• 2011

Rice syrup meal (RSM) was enzymatically hydrolyzed using eight commercial proteases (Protamex, Neutrase, Flavourzyme, Alcalase, Protease M, Protease N, Protease A, Molsin F) for 4 hr at optimum pH and temperature. Proteolytic hydrolysates were examined in supernatant and precipitate using Lowry protein assay, semimicro Kjeldahl method and gravimetric method using weight difference before and after enzymatic hydrolysis. Although RSM contains a high amount of protein (71.2%), only a very small amount of protein was hydrolyzed. Two proteases (Protease M and Protease N) were found to be the most effective in the hydrolysis of RSM protein. In Lowry method, 57.5 and 59.0 mg protein/g RSM were hydrolyzed after Protease M and Protease N treatments, respectively. In gravimetric method, 80.0 and 85.4 mg protein/g RSM were hydrolyzed after Protease M and Protease N treatments. In Kjeldahl method, 67.43 and 70.43 mg protein/g RSM were hydrolyzed after Protamex and Protease N treatments, respectively. For synergistic effect, two or three effective commercial proteases (Protease M, Protease N and Protease A) were applied to RSM at one time. The highest hydrolysis of RSM protein was observed in both Lowry protein assay (80.3 mg protein/g RSM) and gravimetric methods (153.2 mg protein/g RSM) when three commercial proteases were applied at one time, suggesting the synergistic effect of those proteases.

• Food Science and Preservation
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• v.22 no.1
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• pp.84-90
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• 2015

The physicochemical properties and protease activities of spray-dried pineapple juice powders were investigated. The pH, soluble solids, and protease activity of the pineapple juice were pH 5.43, $12.8^{\circ}Brix$, and 4.82 unit/mL, respectively. The optimum pH and temperature of the protease activity from pineapple juice were pH 7.0 and $50^{\circ}C$, respectively. The microencapsulation of pineapple juice was achieved using maltodextrin and alginic acid through spray-drying. The L value and moisture content of the spray-dried powder were higher than those of the freeze-dried powder. The particle size of the freeze-dried powder ($501.57{\mu}m$) was higher than that of the spray-dried powder ($42.58-53.32{\mu}m$). The water absorption and water solubility of the powders were 0.41-0.87, and 90.45-99.76%, respectively. When compared, the protease activities were found to be in the following order : FD (1,297.47 unit/g) > SD-MA-1 (692.08 unit/g) > SD-MA-2 (664.66 unit/g) > SD-MA-3 (642.65 unit/g) > SD-M (633.51 unit/g). In the in vitro dissolution study measurements were conducted for 4 hr in pH 1.2 simulated gastric fluid and pH 6.8 simulated intestinal fluid, using a dissolution tester at $37^{\circ}C$ in 50 rpm. The protease survival of the 3.74-15.69% microencapsulated pineapple juice powders improved with an increase in the treatment concentration of alginic acid.