• Journal of Microbiology and Biotechnology
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• v.17 no.5
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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.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.167-171
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• 2004

We constructed an oligo-d(T) primed directional cDNA library from the Bombyx mandarina whole larvae. In an effort to isolate genes expressed in the B. mandarina, 227 expressed sequence tags (ESTs) were generated by single-pass sequencing from the cDNA library. Sequence analysis showed that 107 clones (47.1%) were classified into known genes and 120 clones (52.9%) were novel transcripts, which are unknown for their function. Of the 107 known genes, the most abundant gene was found to be actin and followed by serine protease in the expression profile. Among these clones, a serine protease homolog (BmSP) which is a class of proteolytic enzymes isolated. Full-length sequence of the BmSP cDNA clone was 922 bp in length and has an open reading frame of 276 amino acids. The conserved histidine, aspatic acid and serine residues forming the catalytic center as well as cysteine residues contributing to three disulphide bonds also were found in Bmsp gene. mRNA expression analysis revealed a high and specific expression of the gene only in midgut tissue, suggesting that BmSP gene is closely associated with the expression of digestive enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.387-394
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• 1983

The factor, which was capable of accelerating the yeast cell wall lysis of the zymolyase(${\beta}-1$, 3-glucanase), was purified to a homogeneous state from the protease fraction of the crude zymolyase by Sephadex G-75 gel filtration and preparative polyacrylamide gel disc electrophoresis. The molecular weight of the purified factor was estimated to be 40,500 by SDS-polylacrylamide gel disc electrophoresis and it's iso-electric point was pH 9.6. The factor was found to be a basic protease consisted of single polypeptide chain with 395 amino acid residues and it showed the $E_{280,cm}^{1%}$ of 11.9 and the molecular extinction coefficient of $4.83{\times}10^4$, respectively.

• Animal Bioscience
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• v.35 no.10
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• pp.1628-1634
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• 2022

Objective: This study focused on the effect of dietary metallo-protease and Bacillus velezensis CE 100 on growth performance, carcass parameters, intestinal microflora, footpad dermatitis (FPD), and manure odor in broiler chickens. Methods: One hundred-ten (two-day-old Ross 308) broiler chicks were randomly assigned to five groups with two replicate pens. The dietary treatments were divided to control, metallo-protease groups (A1, added with 0.1%; A2, added with 0.2%) and B. velezensis CE 100 groups (B1, added with 0.5%; B2, added with 1.0%). Results: The feed intake was decreased in A1 and B2 compared to the other group (p<0.05). The liver weight was lower in B2 than in A2 (p<0.05). The Salmonella in the cecum was decreased in A2 compared to control and A1 (p<0.05). However, the lactic acid bacteria were increased in all treatments (p<0.05). The litter moisture content was decreased in A2, B1, and B2 (p<0.05). The litter quality visual score was increased in all treatments (p<0.05). The FPD score and prevalence were reduced in all treatments (p<0.05). The (CH₃)₂S emission was decreased in all treatments (p<0.05). Conclusion: The present study indicated that both additives improve litter quality and reduce the incidence of FPD. These findings suggest that dietary metallo-protease and B. velezensis CE 100 have the potential to improve the broiler chickens' welfare.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.9-14
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• 2005

Batch enzymatic hydrolysis of egg yolk protein by protease was carried out at laboratory scale coupled to an ultrafiltration module. Effect of ethanol concentrations on the performance of enzymatic hydrolysis was studied to determine the optimum condition of recovery of hydrolysate. The enzymatic hydrolysis was conducted stepwise with following conditions, $50^{\circ}C$, pH 10.0 and pH 6.5. Ethanol concentration was changed from 10 to $40\%$ (w/w). As ethanol concentration was increased, the recovery yield of total solid and protein in enzymatic hydrolysate was also increased. The content of sialic acid and protein in hydrolysate was independent of ethanol concentration. We also investigated the effect of ethanol concentration on the performance of ultrafiltration. As the concentration of ethanol in yolk protein was increased, the recovery yield of product was increased. Ultra­filtration of egg yolk protein hydrolysate was conducted to increase the content of sialic acid. Four ultrafiltation modules were used in this study, and we evaluated the performance of the UF modules. When Amicon module was used, the recovery percentage of total solid in retentate was $6.0\%$, which is the highest among the modules used. In spite of the difference in the recovery yield of total solid, the purity of sialic acid in retentate was about $2.0\%$, which was 5 times higher than that in feed. It was concluded that the recovery yield and the purity of sialic acid did not correlate with the types of modules and the size of MWCO.

• The Korean Journal of Zoology
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• v.39 no.3
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• pp.299-306
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• 1996

The effects of antimetabolite 6-aminonicotinamide on levels of soluble proteins, free amino acids and protease activity in various tissues of quail have been in vestigated. The levels of soluble proteins m liver, heart and pectoral muscle were markedly lowered and the specific activity of protease in kidney and pectoral muscle was markedly increased. The concentrations of aspartic acid / asparagine, alanine, valine, methionine, isoleucine, leucine and lysine in the liver were markedly increased. En the kidney the concentrations of aspartic acid I asparagine, arginine, threonine, alanine, proline and lysine were markedly increased but those of glutamic acid I glutamine were decreased. The concentrations of glutamic acid / glutamine and serine in the heart were reduced but those in glycine and methionine were increased. In the pectoral muscle the concentration of arginine was decreased but the concentration of alanine and threonine was increased. The overall results suggest that antimetabolite 6-aminonicotinamide may act to enhance concentrations of amino acids related to the generation of energy and to depress the biosynthesis of some specific amino acids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1854-1859
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• 2010

Three kinds of Korean traditional Meju were selected and the counts of microorganisms in these Meju were determined. The counts of total aerobic bacteria, lactic acid bacteria and yeasts and molds were 107~108, 106~108 and 107~108 cfu/g, respectively in three Meju and lactic acid bacteria were important microorganisms in the fermentation of Meju. Therefore, we isolated three kinds of dominant lactic acid bacteria from these Meju. They were identified as Leuconostoc mesenteroides (98%, Lm-SMm), Lactobacillus plantarum (99%, Lp-SMm) and Lactococcus lactis (98%, Ll-GAm). Then, enzyme activities and physiological functionalities of three lactic acid bacteria were investigated. Protease, lipase and $\alpha$-amylase activities were detected in three lactic acid bacteria, Ll-GAm showed relatively higher activities than other two lactic acid bacteria. Lm-SMm, Lp-SMm and Ll-GAm showed 45, 48 and 60% of antioxidative activity to 1,1-diphenyl-2-picryhydrazyl (DPPH), and exhibited 45, 67 and 70% of inhibitory effects in HT-29 human colon cancer cells, respectively. These results indicate that three lactic acid bacteria isolated from traditional Meju, especially Ll-GAm are applicable to Meju preparation for soybean paste industry.

• Biomolecules & Therapeutics
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• v.24 no.5
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• pp.529-535
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• 2016

Atopic dermatitis (AD) results from gene and environment interactions that lead to a range of immunological abnormalities and breakdown of the skin barrier. Protease-activated receptor 2 (PAR2) belongs to a family of G-protein coupled receptors and is expressed in suprabasal layers of the epidermis. PAR2 is activated by both trypsin and a specific agonist peptide, SLIGKV-$NH_2$ and is involved in both epidermal permeability barrier homeostasis and epithelial inflammation. In this study, we investigated the effect of lobaric acid on inflammation, keratinocyte differentiation, and recovery of the skin barrier in hairless mice. Lobaric acid blocked trypsin-induced and SLIGKV-$NH_2$-induced PAR2 activation resulting in decreased mobilization of intracellular $Ca^{2+}$ in HaCaT keratinocytes. Lobaric acid reduced expression of interleukin-8 induced by SLIGKV-$NH_2$ and thymus and activation regulated chemokine (TARC) induced by tumor necrosis factor-a (TNF-${\alpha}$) and IFN-${\gamma}$ in HaCaT keratinocytes. Lobaric acid also blocked SLIGKV-$NH_2$-induced activation of ERK, which is a downstream signal of PAR2 in normal human keratinocytes (NHEKs). Treatment with SLIGKV-$NH_2$ downregulated expression of involucrin, a differentiation marker protein in HaCaT keratinocytes, and upregulated expression of involucrin, transglutamase1 and filaggrin in NHEKs. However, lobaric acid antagonized the effect of SLIGKV-$NH_2$ in HaCaT keratinocytes and NHEKs. Topical application of lobaric acid accelerated barrier recovery kinetics in a SKH-1 hairless mouse model. These results suggested that lobaric acid is a PAR2 antagonist and could be a possible therapeutic agent for atopic dermatitis.

• Korean journal of food and cookery science
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• v.6 no.4 s.13
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• pp.1-8
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• 1990

For the purpose of supplying the imformation to improve the acceptability of soy paste as the condiment, the changes of enzyme activity, general component and flavor compounds (Free amino acid, Nucleic acid related compounds, and peptide) during improved soy paste fermentation were determined. The results were as follows; 1. The protease activity during fermentation were increased continuously, but amylase activity were decreased in 45 day fermentation. Cellulase activity were slowly increased until 45 day, and then slowly decreased. 2. Total nitrogen contents were almost constant during fermentation, but amino nitrogem were increased rapidly. Reducing sugar were not constant, but increased in the end of fermentation. PH were decreased to pH 4.97. 3. Total contents of free amino acid as flavor compound were rapidly increased in 10 day fermentation, but were constant in $30{\sim}60$ day. Aspartic acid contents were increased continuously, but glutamic acid were increased slowly until 30 day fermentation and were almost constant. IMP and GMP contents showed increasing pattern during fermentation.

• Applied Biological Chemistry
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• v.19 no.2
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• pp.82-92
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• 1976

The study was carried out to investigate the changes of the various chemical components and the microflora during the aging period of Korean navive Kochuzang. (Red pepper soybean paste) Korean native maeju loaves were separated into surface and inner parts. Three kinds of Korean native Kochuzang were prepared from surface part, inner part, and ordinary of maeju. The selection and the indentification of the high enzyme producing strains from the microflora and characteristics of their enzymes were studied. I. The changes of the various chemical components during the aging period of Kochuzang. 1) The changes of pH in the 3 kinds of Kochuzang displayed rapid decrease for the first 10 days after preparing and gradual curve of decrease until 60 days, but slight increase for the next 30 days. The pH of the surface part Kochuzang was lower than that of inner part or ordinary Kochuzang. 2) The total acid contents in the 3 kinds of Kochuzang showed gradual increase until the 60 days but it slowly reduced after this time. 3) The total nitrogen contents in the 3 kind of Kochuzang showed gradual inerease up to the 60 days, but slight decrease after this time. 4) The changes of trichloroacetic acid soluble nitrogen in the 3 kinds of Kochuzang showed a remarkable increase for the first 10 days, however gradual increase after this time. 5) The increase of amino nitrogen contents in the 3 kinds of Kochuzang seemed to be remarkable until the first 30 days, however to be less remarkable after this time. 6) The contents of reducing sugar in the 3 kinds of Kochuzang showed remarkable increase until the first 50 days and it slowly reduced after this time. II. The changes of microflora during the aging period of Kochuzang. 1) Aerobic, anaerobic bacteria and mold in the 3 kinds of Kochuzang were increased until the first 30 to 40 days, but they were reduced after this time. 2) No yeast in the three kinds of Kochuzang appeared until the first 20 days. Yeast were proved to grow, when the pH value was decreased below 5.4 after the 30 days. Yeasts in the surface part and ordinary Kochuzang were gradually increased and those in the inner part Kochuzang were decreased as aging. III. The selection and identification of high amylase and protease producing strains from the microflora during the aging period of Kochuzang. 1) The amylase and protease highly producing strains from microflora were identified as Bacillus subtilis-P, Bacillus subtilis-G, Bacillus licheniformis-K, Aspergillus oryzae-B. 2) Amylase activity of Aspergillus oryzae-B was highest among the strains and the strains in order of the higher activity to the lower one were Bacillus subtilis-P Bacillus licheniformis-K, Bacillus subtilis-G. Protease activities of Aspergillus oryzae-B and Bacillus subtilis-P were about the same and the strains in order of the higher activity to the lower one were Bacillus licheniformis-K, Bacillus subtilis-G. 3) Amylase activity was inhibited more than protease activity was with NaCl concentration. Amylase activity was inhibited by 45 to 65 percent and protease activity by 40 to 46 percent at the concentration of 15 percent NaCl, which was the average concentration of NaCl in Kochuzang.