• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.195-201
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• 2000

Glucoamylase of Saccharomyces diastaticus is produced as a large precursor composed of signal peptide (21 amino acid residues), Thr and Ser-rich region and functional glucoamylase. To evaluate the utility of the glucoamylase signal peptide (GSP) for the secretion of foreign proteins, four types of GSP mutants (ml : Pro-18 longrightarrowLeu-18, m2 : Tyr-13 longrightarrowLeu, m3 : Ser-9longrightarrowLeu-9, m4 : Asn-5 longrightarrowPro-5) were constructed and secretion efficiency of each mutant was compared with that of native GSP by the expression and secretion of Bacillus subtilis CMCase under the control of GAP in N-terminal domain and hydrophobic domain. n mutant 4, a polar amino acid was replaced by a helix - breaking Pro residue. CMCase activity assay and Western blot analysis revealed that CMCase secretion by GSP mutants replaced by Leu were increased compared with native GSP. In the case of m2 and m3, the substitution of Leu for Tyr-13 and Ser-9 in the hydrophobic region resulted in a twofold increase in the extracellular CMCase activity.

• Mycobiology
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• v.29 no.3
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• pp.173-175
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• 2001

The fruit body of Ramaria botrytis DGUM 29001 was used to determine enzyme activities of fruit body. The specific activity of laccase was the highest(6.5 unit/mg$\cdot$protein) and that of $\alpha$-amylase and xylanase was relatively high. However, little or no enzyme activity of $\beta$-glucosidase, CMCase, exo-$\beta$-1,4-glucanase, chitinase, lipase and protease was found.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.3
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• pp.80-89
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• 2007

Two endogenous endo-${\beta}$-1,4-D-glucanase (EGase, EC 3.2.1.4) cDNAs were cloned from the midgut of the earthworm Eisenia anderi, and named EaEG2 and EaEG3, respectively. A sequence of 1,368 bp was determined and the coding region is composed of 456 amino acid residues including the initiation methionine. The N-terminal region of 20 residues in the deduced sequence was regarded as the signal peptide. These EGases belong to glycosyl hydrolase family 9 (GHF9) and showed high levels of identity(51-55%) with selected termite, cockroache, crayfish and mollusc EGases. The EGases of earthworm consist of three consensus catalytic domains found in most microbial cellulases. A phylogenetic tree was constructed using the deduced amino acid sequence data matched through the BLASTX program and showed that GHF9 families could be divided into five groups of arthropoda, bacteria, plant, annelida and mollusc.

• Mycobiology
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• v.38 no.2
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• pp.108-112
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• 2010

To investigate the possible roles of LAMMER kinase homologue, Lkh1, in Schizosaccharomyces pombe, whole proteins were extracted from wild type and lkh1-deletion mutant cells and subjected to polyacrylamide gel electrophoresis. Differentially expressed proteins were identified by tandem mass spectrometry (MS/MS) and were compared with a protein database. In whole-cell extracts, 10 proteins were up-regulated and 9 proteins were down-regulated in the mutant. In extracellular preparations, 6 proteins were up-regulated in the lkh1+ null mutant and 4 proteins successfully identified: glycolipid anchored surface precursor, $\beta$-glucosidase (Psu1), cell surface protein, glucan 1,3-$\beta$-glucosidase (Bgl2), and exo-1,3 $\beta$-glucanase (Exg1). These results suggest that Lkh1 is involved in regulating cell wall assembly.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.275-282
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• 1997

The prcx.iuction of extracellular 1,4-${\beta}$-glucanase by Cellulomonas sp. CS1-1 on microcrystalline cellulose, sigmacell was maximal after 5-day cultivation as 280 units/mL, which was three times higher than the level produced on carboxymethyl cellulose. A carboxymethyl cellulase containing the carbohydrate of 8.2% was purified from the culture filtrate by successive procedures of column chromatographies. Purification factor was calculated as 22-folds with the specific carboxymethyl cellulase activity of 31.9 units/mg. The molecular weight and isoelectric point of the purified enzyme were 54,000 and pI 5.4, respectively. The optimal pH and temperature were 6.0 and $45^{\circ}C$, and the enzyme was stable between pH 6.5 and 7.5 and below $50^{\circ}C$. The estimated Km and Vmax were 10 mg/mL and $6.25{\mu}mol/min$ for carboxymethyl cellulose and 30.3 mg/mL and $2.85{\mu}mol/min$ for sigmacell, respectively. The enzyme was partially inhibited by $Ag^+$, $Zn^{+{+}}$, $Fe^{+{+}}$ and EDTA, while completely inhibited by $Cd^{+{+}}$ and $Hg^{+{+}}$ at 1 mM concentration.

• KSBB Journal
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• v.18 no.5
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• pp.352-355
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• 2003

${\beta}$-(1,6)-Branched ${\beta}$-(1,3)-D-glucans are known to enhance the immune system in human body, and in most cases have higher molecular weights over 1 MDa. In order to enhance the efficacy of glucans by decreasing their molecular weights, sonication, acid treatment, and enzymatic hydrolysis were tested and compared in this work. Treatment of sonication was effective to decrease the molecular weight to the extent of several dozens of kilo-daltons, but have a risk to disorder the triple helical structure of the glucans. Acid treatment was also an effective method to degrade polysaccharides, but ${\beta}$-(1,6)-branched of the glucan molecules was found to be also hydrolyzed. Treatment of ${\beta}$-(1,3)-glucanase was an effective method to decrease the molecular weight in mild conditions, but could not hydrolyse the highly ${\beta}$-(1,6)-branched ${\beta}$-(1,3)-glucans efficiently.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.354-361
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• 2018

This study was carried out to isolate soil bacteria with antimicrobial activity and evaluate antimicrobial substances produced by isolated bacteria. Among many isolates Bacillus subtilis DS660 and Paenibacillus polymyxa DS842 showed high antimicrobial activities against 6 species of microbial residents on human skin and 3 species of pathogenic bacteria. DS660 and DS842 showed 15.3~26.8 and 11.3~27.5 mm of inhibition zone diameter, respectively on nutrient agar medium against most target bacteria and fungi. DS660 and DS842 produced $57{\pm}8$ and $170{\pm}15{\mu}mol/ml$ of siderophore, respectively as an antimicrobial substance. Analysis of ethyl acetate extract of culture supernatants of DS660 and DS842 suggested production of glycolipid biosurfactant which reduced surface tension of culture supernatant of DS660 and DS842 from 60.0 to 40.3 and 30.3 mN/m, respectively. DS660 and DS842 also showed $169.2{\pm}9.9$ and $357.2{\pm}13.7nmol/min/mg$ protein of ${\beta}-1,3$-glucanase activity, respectively, and hydrolyzed cell wall components of 3 bacterial species. These results suggest that B. subtilis DS660 and P. polymyxa DS842 may be utilized as an environment-friendly biocontrol agent against some skin microbes and pathogenic bacteria.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.407-415
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• 2012

An endophytic bacterium, Bacillus thuringiensis GS1, was isolated from bracken (Pteridium aquilinum) and found to have maximal production of chitinase (4.3 units/ml) at 5 days after culture. This study investigated the ability of B. thuringiensis GS1 to induce resistance to Rhizoctonia solani KACC 40111 (RS) in cucumber plants. Chitinase activity was greatest in RS-treated plants at 4 days. ${\beta}$-1,3-Glucanase activity was highest in GS1-treated plants at 5 days. Guaiacol peroxidase (GPOD) activity increased continuously in all treated plants for 5 days. Ascorbate peroxidase (APX) activity in RS-treated plants was increased 1.5-fold compared with the control at 4 days. Polyphenol oxidase (PPO) activity in RS-treated plants was increased 1.5-fold compared with the control at 3 days. At 5 days after treatment, activity staining revealed three bands with chitinase activity (Ch1, Ch2, and Ch3) on SDS-PAGE of cucumber plants treated with GS1+RS, whereas only one band was observed for RS-treated plants (Ch2). One GPOD isozyme (Gp1) was also observed in response to treatment with RS and GS1+RS at 4 days. One APX band (Ap2) was present on the native-PAGE gel of the control, and GS1- and GS1+RS-treated plants at 1 day. PPO bands (Po1 and Po2) from RS- and GS1+RS-treated plants were stronger than in the control and GS1-treated plants upon native-PAGE at 5 days. Taken together, these results indicate that the induction of PR proteins and defense-related enzymes by B. thuringiensis GS1 might have suppressed the damping-off caused by R. solani KACC 40111 in cucumber plants.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.660-661
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• 2001

Pseudomonas sp. GRC3 produced extracellular chitinase(s) and ${\beta}$-1,3-glucanase(s), possible biocontrol agents. Both of enzymes appeared to inhibit the growth of plant phathogens, especially Phytophthora capsici. Antifungal activities of Pseudomonas sp. GRC3 determined was more than 78% inhibition rate against P. capsici.

• Korean Journal of Food Science and Technology
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• v.12 no.4
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• pp.254-262
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• 1980

A series of experiment were carried out to separate the factor accelerating the lysis of cell wall of $Saccharomyces\;sak{\acute{e}}$ from the preparation of crude zymolyase obtained from Arthrobacter luteus. An attempt was also made to purify the enzyme which is essential for the study on the separation of the factor. The results are summarized as follows: 1. Crude zymolyase was fractionated 5 peaks $(A{\sim}E)$ containing three peaks $(A{\sim}C)$ passed through the column by the chromatography on Biogel CM-30. 2. Among the five peaks, peak E (protease fraction) was found to contain the factor accelerating the lytic activity of the zymolyase. 3. L-c fraction purified in almost free form from the nonlytic ${\beta}-1$, 3-glucanase, protease and inert protein by the affinity adsorption chromatography with Sephadex G-75 gel was obtained from zymolyase fraction (peak D). When it was subjected to polyacrylamide gel disc electrophoresis, only one clear protein band was observed at pH 4. 5, but still detected two or more band at pH 8. 3.