• Korean Journal of Microbiology
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• v.18 no.1
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• pp.15-19
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• 1980

In order to study on the pigment and protease of Serratia marcescens, the correlation between protease activity and pigment formation was investigated. The results are as follows ; (1) The protease activity exhibitied two pH optima 6.0 and 7.5, respectively. (2) The optimal temeprature of proteolytic activity was $45^{\circ}C$. With these-results, it is suggested that the proteolytic enzymes of Serratia masrecescens is stable at neutral pH range and more active at the high temeprature than lthat of otehr proteolytic enzymes.

• CELLMED
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• v.4 no.1
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• pp.6.1-6.12
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• 2014

Anthrax is the deadly disease for human being caused by Bacillus anthracis. Instantaneous research work on the mode of infection of the organism revealed that different proteases are involved in different steps of pathogenesis. Present study reports the in silico characterization and the detection of pathogenic proteases involved in anthrax infection through protein-protein interaction. A total of 13 acid, 9 neutral, and 1 alkaline protease of Bacillus anthracis were selected for analysing the physicochemical parameter, the protein superfamily and family search, multiple sequence alignment, phylogenetic tree construction, protein-protein interactions and motif finding. Among the 13 acid proteases, 10 were found as extracellular enzymes that interact with immune inhibitor A (InhA) and help the organism to cross the blood brain barrier during the process of infection. Multiple sequence alignment of above acid proteases revealed the position 368, 489, and 498-contained 100% conserved amino acids which could be used to deactivate the protease. Among the groups analyzed, only acid protease were found to interact with InhA, which indicated that metalloproteases of acid protease group have the capability to develop pathogenesis during B. anthracis infection. Deactivation of conserved amino acid position of germination protease can stop the sporulation and germination of B anthracis cell. The detailed interaction study of neutral and alkaline proteases could also be helpful to design the interaction network for the better understanding of anthrax disease.

• Korean Journal of Microbiology
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• v.26 no.4
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• pp.355-361
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• 1988

The aims of the present studies were to understand the physiolosical and genetic characters of Streptomyces sp. isolated from soil. It revealed that Streptomyces sp. SMF301 had very fast growth rate and produced extracellular protease and heavily sporulated on rich media. It also showed $\beta$-lactamase activity and pigment production. Nonsporulating mutants were isolated after NTG or acriflavin treatment and their characters were compared with the parent strain. It was found that the mutants obtained by acriflavin treatment and ghier characters were compared with the parent strain. It was found that the mutants obtained by acriflavin treatment lost the pigment formation and $\beta$-lactamase production. Protease actibity of the mutant was lowered and the pH optimum was changed toward neutral. It was found that the changes were resulted from the reduction of alkaline protease biosynthesis in the bald mutant. Therefore it is considered that sporulation, pigment formation, $\beta$-lactamase production, and alkaline protease production in Streptomyces sp. might be controlled with a closely related relationship.

• Journal of Life Science
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• v.16 no.4
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• pp.598-604
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• 2006

The $Ca^{2+}-activated$ neutral protease calpain induced proteolysis has been suggested to play a role in certain cell growth regulatory proteins. Cyclin proteolysis is essential for cell cycle progression. D-type cyclins, which form an assembly with cyclin-dependent kinases (cdk4 and cdk6), are synthesized earlier in G1 of the cell cycle and seem to be induced in response to external signals that promote entry into the cell cycle. Here we show that cyclin D3 protein levels are regulated at the posttranscriptional level by calpain protease. Treatment of human breast carcinoma MDA-MB-231 cells with lovastatin and actinomycin D resulted in a loss of cyclin D3 protein that was completely reversible by the peptide aldehyde calpain inhibitor, LLnL. The specific inhibitor of the 26S proteasome, lactacystin, the lysosome inhibitors, ammonium chloride and chloroquine, and the serine protease inhibitor, phenylmethylsulfonylfluoride (PMSF), did not block the degradation of cyclin D3 by lovastatin and actinomycin D. Results of in vitro degradation of cyclin D3 by purified calpain showed that cyclin D3 protein is degraded in a $Ca^{2+}-dependent$ manner, and the half-life of cyclin D3 protein was dramatically increased in LLnL treated cells. These data suggested that cyclin D3 protein is regulated by the $Ca^{2+}-activated$ protease calpain.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.59-64
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• 1994

The production and the characteristics of protease produced by Bacillus sp. SH-8 and Bacillus sp. SH-8M were investigated under the different pH conditions. Bacillus sp. SH-8 and Bacillus sp. SH-8M showed the maximum activity of protease at 60 hours(70 units/ml) AND 96 houre(50 units/ml) cultivation, respectively, under the alkaline condition(pH 10.2). However, Bacillus sp. SH-8M exhibited the maximum activities in 8 days cultivation at pH 6.9 and in 6 days cultivation at pH 7.7 Bacillus sp. SH-8M showed the protease activity at the pH change from alkaline to neutral condition, whereas Bacillus sp. SH-8 did not. In addition. all the enzymatic characteristics of protease produced by Bacillus sp. SH-8 and Bacillus sp. SH-8M were similar with the regardless of different pH conditions.

• Journal of Pharmaceutical Investigation
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• v.18 no.3
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• pp.125-131
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• 1988

This study was undertaken to investigate the proteolytic enzyme from Neungee mushroom [Sarcodon aspratus (Berk) S. Ito]. The proteolytic activity of Neungee was higher than other several edible mushrooms under various pHs. The potency of proteolytic enzyme of Neungee was same as the digestive drugs containing protease. So the proteolytic activity of the enzyme was increased in neutral or weak alkaline pH, whose characteristics would be alkaline protease. The specific activity of the purified enzyme obtained by using Tris acryl CM-cellulose ion exchange increased 20 times as compared with that of the crude extract. The proteolytic enzyme was stable at room temperature, but decomposition was fast when incubated at higher temperature more than $40^{\circ}C$. The half life of the enzyme was longest in neutral pH and rate constant was increased in acidic or alkaline solution.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.101-106
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• 2001

Alpha-amylase and glucoamylase activities were higher in koji with 40% water than that with 30 and 50% water, and A. oryzae exhibited very high alpha-amylase and glucoamylase activities compared to A. sojae and A. niger. Acidic, neutral and alkaline protease activities also showed higher activities in koji prepared with flour, Korean wheat powder and soybean powder with 40% water based on the weight of the sample. Alpha-amylase, acidic, neutral and alkaline protease activities of all the koji samples according to incubation periods increased until 3~4 days of incubation and maintained nearly the same level or slightly decreased after 5 days of incubation. The protease activities of A. oryzae and A. sojae showed nearly the same trend regardless of differences in substrate conditions and koji materials, but those of A. niger showed a lower activity than those of A. oryzae and A. sojae. These results suggest that the preparation of koji is possible with Korean wheat powder and soybean powder and A. sojae can be utilized as a new strain for fermented foods using soybean as the main materials to increase functional properties and produce products having a new taste and flavor.

• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.33-40
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• 1978

Immobilization of alkaline protease was investigated by absorbing the enzyme on adsorbents. Alkaline protease was adsorbed on silica gel selected as a carrier to immobilize the enzyme. In this study, properties of the immobilized enzyme were compared with those of the soluble enzyme. 1) The optimum pH (10.0) of the enzyme was not changed, but the activity was increased at alkaline pH by immobilization. 2) The optimum temperature of the immobilized enzyme was shifted from 50$^{\circ}C$ to 45$^{\circ}C$, while the temperature-activity Profile became broader than those of the soluble enzyme. 3) The pH stability of the immobilized enzyme was significantely increased at pH 4.0, althouth it did not change in the neutral and alkaline pH region. 4) The heat stability of the enzyme was enhanced in the temperature range of 55$^{\circ}C$∼65$^{\circ}C$ by the immobilization. 5) The immobilized enzyme retained 40％ of its original activity after repetitive use for 6 times. 6) The enzyme stability was greately improved for a prolonged storage at 4$^{\circ}C$.

• Korean Journal of Microbiology
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• v.10 no.3
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• pp.106-108
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• 1972

The enzyme was produced by Asp.oryzae SHW 131. the enzymatic properties of .alpha.-amylase are following : 1) Crystallization of .alpha.-amylase is formed of longish square. 2) The range of stable pH is 5-10 and optimum ph is 5.5. 3) It is very unstable enzyme about EDTA and protection by $Ca^{++}$ ion and best activated at $50^{\circ}C$ about temperature. 4) Asp.oryzae SHW 131 produced .alpha.-amylase with acid-protease, neutral-protease and tepid-alkalin-protease.

• Korean Journal of Microbiology
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• v.10 no.3
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• pp.105-105
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• 1972

The enzyme was produced by Asp.oryzae SHW 131. the enzymatic properties of .alpha.-amylase are following : 1) Crystallization of .alpha.-amylase is formed of longish square. 2) The range of stable pH is 5-10 and optimum ph is 5.5. 3) It is very unstable enzyme about EDTA and protection by $Ca^{++}$ ion and best activated at $50^{\circ}C$ about temperature. 4) Asp.oryzae SHW 131 produced .alpha.-amylase with acid-protease, neutral-protease and tepid-alkalin-protease.