• The Korean Journal of Mycology
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• v.23 no.2 s.73
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• pp.129-138
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• 1995

DNA fragment being able to restore in vitro activity of ${\beta}-1,3-glucan$ synthase was cloned by transformation of the Saccharomyces cerevisiae LP353 mutant strain with genomic library constructed in the YCp50. For the selection of transformants which showed no detectable phenotype linked to recovery of the defect in ${\beta}-1,3-glucan$ synthase activity, the colony autoradiography was succesfully applied. The restriction map of the cloned DNA fragment, which is 8.5-kb in length, was constructed. Both the YEplac195 and the YCp50 carrying the 8.5-kb fragment increased ${\beta}-1,3-glucan$ synthase activity of LP353 by two fold. Neither the YEplac195 nor the YCp50 carrying the 8.5-kb DNA fragment, however, complemented the temperature-dependent osmotic sensitivity which is another distinctive phenotype of LP353. Subcloning experiments indicated that a functional region was located in 4.8-kb BglII-KpnI fragment. The 4.8-kb fragment was also able to increase the level of ${\beta}-1,3-glucan$ content in cell wall as well as the resistance of cells to cell wall lytic enzyme, ${\beta}-1,3-glucanase$. The growth rate of the LP353 with 4.8-kb fragment was almost same as that of wild type strain in liquid medium with 1.2 M sorbitol at nonpermissive temperature. Taken these results together, the 4.8-kb fragment seemed to contain the BGS2 gene for ${\beta}-1,3-glucan$ synthase activity in yeast S. cerevisiae.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1359-1366
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• 2012

A strain of Streptomyces cavourensis subsp. cavourensis (coded as SY224) antagonistic to Colletotrichum gloeosporioides infecting pepper plants was isolated. SY224 produced lytic enzymes such as chitinase, ${\beta}$-1,3-glucanase, lipase, and protease in respective assays. To examine for antifungal activity, the treatments amended with the nonsterilized supernatant resulted in the highest growth inhibition rate of about 92.9% and 87.4% at concentrations of 30% and 10%, respectively. However, the sterilized treatments (autoclaved or chloroform treated) gave a lowered but significant inhibitory effect of about 63.4% and 62.6% for the 10% supernatant concentration, and 75.2% and 74.8% for the of 30% supernatant concentration in the PDA agar medium, respectively, indicative of the role of a non-protein, heat stable compound on the overall effect. This antifungal compound, which inhibited spore germination and altered hyphal morphology, was extracted by EtOAc and purified by ODS, silica gel, Sephadex LH-20 column, and HPLC, where an active fraction was confirmed to be 2-furancarboxaldehyde by GS-CI MS techniques. These results suggested that SY224 had a high potential in the biocontrol of anthracnose in pepper, mainly due to a combined effect of lytic enzymes and a non-protein, heat-stable antifungal compound, 2-furancarboxaldehyde.

• 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.

• 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.

• 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.

• 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.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.63-69
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• 2010

The effect of Acibenzolar-S-methyl (ASM) and Rahnella aquatilis Ra39 against apple fire blight disease caused by Erwinia amylovora were tested as a possible alternative to streptomycin. In vitro studies, no inhibition effect against the pathogen was found when ASM was tested. Under greenhouse conditions, application of R. aquatilis Ra39 with the highly susceptible M26 rootstock resulted in a marked disease suppression. Application of ASM and strain Ra39 caused a high decrease of the disease, 82% and 58% respectively; this was correlated with a reduction of the growth of the pathogen within host plants up to 64% and 49.5% respectively. Further studies in the field under artificial infection condition during full bloom revealed that application of ASM and R. aquatilis Ra39 with Gala variety resulted in a control effect up to 21 and 29% respectively. In physiological studies, enhanced activities of PR-proteins (chitinase and $\beta$-1, 3-glucanase) were detected, which are well known as biochemical markers for systemic acquired resistance. Application of ASM to apple shoots caused the highest chitinase activity followed by strain Ra39. The enzyme activity was increased after 2, 4 and 6 days from application. In addition, ASM-treatment caused the higher $\beta$-1, 3-glucanase activity than strain Ra39. Maximum enzyme activity was recorded after 6 days from application and then decreased after 8 and 10 days from application.

• 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.

• 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.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.1
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• pp.15-20
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• 2006

Biological control by chitinolytic microorganisms is being evaluated as management options for soilborne diseases. Forty kilograms of chitin compost (CTC) and control compost (CC) were amended on tomato plots ($15m{\times}0.5m$) 7 d before transplanting to evaluate enzymatic activities and the control of Fusarium wilt. Samples were taken on day 1, 3, 5, and 7, the day 1 corresponded to the 66 d after transplanting, the day on which the initial wilting symptoms occurred in plants of CC treated plots. The chitinase activity in soil of CTC was always higher compared to the control. Pathogenesis related (PR) protein (chitinase, ${\beta}$-1, 3-glucanase and peroxidase) activities in tomato roots in CC increased every day and showed marked differences compared to CTC. Wilting symptoms (96 d after transplanting) were reduced by 25% in CTC compared to the control. Protection of tomato plant may be correlated with the high levels of soil enzyme activities resulting from the chitin compost.