• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.113-118
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• 1993

Fro the purpose of producing glouse from cellobiose or oligo saccharide and obtaining genetic information of beta-1,4-glucosidase gene, alpha beta-1,4-glucosidase gene of Pseudomonas sp. LBC505, potent cellulase complex and xylanase producing strain, was cloned in Esherichia coli and Bacillus subtilis into pUC19 and pBD64, respectively. Recombinant plasmid pGL1 contained 1.2kb EcoRI fragment was isolated from transformants forming blue color around colony on LB agar plate containing 20 ng/ml of 5-bromo-4-chloro-3-indolyl-beta-D-glucopyranoside(X-glu) and ampicillin.

• Journal of Microbiology and Biotechnology
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• v.25 no.1
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• pp.44-49
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• 2015

Thermostable enzymes derived from Thermotoga maritima have attracted worldwide interest for their potential industrial applications. Structural analysis and docking studies were preformed on T. maritima β-glucosidase enzyme with cellobiose and pNP-linked substrates. The 3D structure of the thermostable β-glucosidase was downloaded from the Protein Data Bank database. Substrates were downloaded from the PubCehm database and were minimized using MOE software. Docking of BglA and substrates was carried out using MOE software. After analyzing docked enzyme/substrate complexes, it was found that Glu residues were mainly involved in the reaction, and other important residues such as Asn, Ser, Tyr, Trp, and His were involved in hydrogen bonding with pNP-linked substrates. By determining the substrate recognition pattern, a more suitable β-glucosidase enzyme could be developed, enhancing its industrial potential.

• Korean Journal of Microbiology
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• v.44 no.1
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• pp.56-62
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• 2008

Two hundred and sixty-eight bacterial strains were isolated from pine mushroom (Tricholoma matsutake) basal soil. In the course of screening for antifungal activity against seven plant pathogenic fungi (Alternaria panax, Botrytis cinerea, Colletotrichum gloeosprioides, Fusarium oxysporum, Phytopthora capsici, Pythium ultimum, Rizoctonia solani) of isolates, strain KM1-15 showed strong antibiotic activity against Alternaria panax and Colletotrichum gloeosprioides. In determining its relationship on the basis of 16S rDNA sequence, KM1-15 strain was most closely related to Bacillus $koguryoae^T$ (AY904033) (99.62%). When assayed with the API 50CHE Kit, unlike Bacillus koguryoae, it is positive for utilization of L-arabinose, cellobiose, inulin, and D-turanose. Results of cellular fatty acid analysis showed that major cellular fatty acids were 15:0 anteiso (35.78%) and 17:0 anteiso (17.97%). In particular, hydroxyl fatty acids such as 13:0 iso 3-OH, 14:0 iso 3-OH, 15:0 iso 3-OH, and 17:0 iso 3-OH were only restricted to strain KM1-15. DNA G+C content was 43.7 mol% and quinone system was MK-7 (100%) in strain KM1-15.

• Mycobiology
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• v.43 no.1
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• pp.57-62
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• 2015

${\beta}$-Glucosidase, which hydrolyzes cellobiose into two glucoses, plays an important role in the process of saccharification of the lignocellulosic biomass. In this study, we optimized the activity of ${\beta}$-glucosidase of brown-rot fungus Fomitopsis pinicola KCTC 6208 using the response surface methodology (RSM) with various concentrations of glucose, yeast extract and ascorbic acid, which are the most significant nutrients for activity of ${\beta}$-glucosidase. The highest activity of ${\beta}$-glucosidase was achieved 3.02% of glucose, 4.35% of yeast extract, and 7.41% ascorbic acid where ascorbic acid was most effective. The maximum activity of ${\beta}$-glucosidase predicted by the RSM was 15.34 U/mg, which was similar to the experimental value 14.90 U/mg at the 16th day of incubation. This optimized activity of ${\beta}$-glucosidase was 23.6 times higher than the preliminary activity value, 0.63 U/mg, and was also much higher than previous values reported in other fungi strains. Therefore, a simplified medium supplemented with a cheap vitamin source, such as ascorbic acid, could be a cost effective mean of increasing ${\beta}$-glucosidase activity.

• Korean Journal of Microbiology
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• v.29 no.2
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• pp.85-91
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• 1991

.betha.-1,4-D-Glucan glucanohydrolase(EC 3.2.1.4;F-II-IV) purified from Trichoderma koningii was identified as a glycoprotein containing 9% carbohydrate. Isoelectric point of the enzyme was estimated to be 4.9 and molecular weight was determined to be approximately 58,000. The porducts of p-nitrophenyl-cellobioside ($PNPG_{2}$) catalyzed by the enzyme were p-nitrophenol(PNP) and p-nitrophenyl-glucoside($PNPG_{1}$). The Km value for $PNPG_{2}$ was estimated to be 0.97 mM in case of the holoside lindage and 10.4 mM in case of the aglycon linkage and their kcat values were $1.8*10^{5}$$ min^{-1}$ and $7.5*10^{5}$ $min^{-1}$ respectively. The product of p-nitrophenyl cellotriose($PNPG_{3}$) was only $PNPG_{1}$. The Km value for $PNPG_{3}$ was 69.5 .$\mu$M and kcat was $1*10^{8}$ $min^{-1}$ which implicates that the enzyme have higher affinity and higher hydrolysis rate toward $PNPG_{3}$ than toward $PNPG_{2}$. The enzyme showed its optimal activity at pH 4.0-4.5 and at 60.deg.C. The effect of gluconolactone on the activity toward $PNPG_{2}$ showed competitive inhibition pattern but glucose and cellobiose did not. The enzyme contained a high content of acidic and hydroxylated amino acids in contrast to basic amino acids.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.905-912
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• 2007

A novel ${\beta}-glucosidase$ gene, bglA, was isolated from uncultured soil bacteria and characterized. Using genomic libraries constructed from soil DNA, a gene encoding a protein that hydrolyzes a fluorogenic analog of cellulose, 4-methylumbelliferyl ${\beta}-D-cellobioside$ (MUC), was isolated using a microtiter plate assay. The gene, bglA, was sequenced using a shotgun approach, and expressed in E. coli. The deduced 55-kDa amino acid sequence for bglA showed a 56% identity with the family 1 glycosyl hydrolase Chloroflexus aurantiacus. BglA included two conserved family 1 glycosyl hydrolase regions. When using $p-nitrophenyl-{\beta}-D-glucoside$ (pNPG) as the substrate, the maximum activity of the purified ${\beta}-glucosidase$ exhibited at pH 6.5 and $55^{\circ}C$, and was enhanced in the presence of $Mn^{2+}$. The $K_m\;and\;V_{max}$ values for the purified enzyme with pNPG were 0.16 mM and $19.10{\mu}mol/min$, respectively. The purified BglA enzyme hydrolyzed both pNPG and $p-nitrophenyl-{\beta}-D-fucoside$. The enzyme also exhibited substantial glycosyl hydrolase activities with natural glycosyl substrates, such as sophorose, cellobiose, cellotriose, cellotetraose, and cellopentaose, yet low hydrolytic activities with gentiobiose, salicin, and arbutin. Moreover, BglA was able to convert the major ginsenoside $Rb_1$ into the pharmaceutically active minor ginsenoside Rd within 24 h.

• Mycobiology
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• v.34 no.2
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• pp.108-110
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• 2006

To understand the ability of producing cellulolytic enzyme activity in the sapstaining fungi, four species of Ophiostoma and two species of Leptographium were investigated in the culture media containing each of cellulose substrates such as CM-cellulose, Avicel and D-cellobiose and each of chromogenic dyes such as Congo-Red, Phenol Red, Remazol Brilliant Blue and Tryphan Blue. When the fungi were grown for $5{\sim}7$ days at $25^{\circ}C$, the formation of clear zone by chromogenic reaction around the margin of the fungal colony was demonstrated in all the culture media Congo-Red containing CM-cellulose. There was difference in the formation of clear zone among the dyes. Only Ophiostoma setosum and Leptographium spp. showed cellulolytic activity to the three substrates. Overall, the results of this study show that ophiostomatoid sapstaining fungi can produce cellulolytic enzymes.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.745-752
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• 2007

A $\beta$-glucosidase from the algal lytic bacterium Sinorhizobium kostiense AFK-13, grown in complex media containing cellobiose, was purified to homogeneity by successive ammonium sulfate precipitation, and anion-exchange and gel-filtration chromatographies. The enzyme was shown to be a monomeric protein with an apparent molecular mass of 52 kDa and isoelectric point of approximately 5.4. It was optimally active at pH 6.0 and $40^{\circ}C$ and possessed a specific activity of 260.4 U/mg of protein against $4-nitrophenyl-\beta-D-glucopyranoside$(pNPG). A temperature-stability analysis demonstrated that the enzyme was unstable at $50^{\circ}C$ and above. The enzyme did not require divalent cations for activity, and its activity was significantly suppressed by $Hg^{+2}\;and\;Ag^+$, whereas sodium dodecyl sulfate(SDS) and Triton X-100 moderately inhibited the enzyme to under 70% of its initial activity. In an algal lytic activity analysis, the growth of cyanobacteria, such as Anabaena flos-aquae, A. cylindrica, A. macrospora, Oscillatoria sancta, and Microcystis aeruginosa, was strongly inhibited by a treatment of 20 ppm/disc or 30 ppm/disc concentration of the enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.423-427
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• 1992

During the cultivation of Penicillium verruculosum in the medium containing xylan as a sole carbon source for 26 days, xylanolytic activity and some changes were investigated. Protein content and xylanolytic activity, p-Nitrophenyl-$\beta$-D-xylopyranoside (PNPX), p-Nitrophenyl-$\beta$ -D-glucopyranoside (PNPG) hydrolytic activities were increased until 8 days but reducing sugar content was not correlated to protein content. When crude proteins from the culture broth were separated on SDS-PAGE, distribution of proteins was different from the culture broth of cellobiose octaacetate (COA) medium. The culture broth of xylan medium had high hydrolytic activity on xylan but not on cellulose. Furthermore, xylanolytic products were showed xylose, xylobiose and oligosaccharides on thin layer chromatography, and xylobiose was major product. Those result suggested that xylanolytic activity of culture broth was endo-type hydrolysis. Optimum temperatures of xylanolytic activity and PNPX hydrolytic activity of culture broth were 50~6$0^{\circ}C$ and 60~7$0^{\circ}C$, respectively and optimum pHs were 3.0~4.0 and 4.0~5.0, respectively.

• Journal of fish pathology
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• v.20 no.2
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• pp.109-117
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• 2007

This study was performed to identity non hemolytic streptococcus from cultured flounder (Paralichthys olivaceus) with Streptococcosis in the Jeju island. The result of BIOLOGTM test was Streptococcus uberis that simility of 0.5 and 98% identified in MicroLogTM system (Release 4.05). Carbohydrate utility pattern was dextrin, N-acetyl-D-glucosamine, arbutin, maltose, maltotriose, D-cellobiose, D-fructose, D-mannose, α-D-glucose, D-mannitol, β-methyl D-glucoside, salicin, sucrose, D-trehalose, pruvatic acid methyl ester, mono-methyl succinate, glycerol. In addition hemolysis test for S. parauberis and were S. iniae hemolysis in BAP (Blood agar plate). Antibiotic test for S. parauberis were Ampicillin, Amoxicillin and Fluoroquinolone sensitivity. Mutiplex PCR assay were detected S. pauberis (718 bp), S. iniae (870 bp) L. garviae (1,100 bp). Dectected S. parauberis (718 bp) were result of 16S rRNA sequence identified with S. parauberis (Gene bank accession number X89967). All isolated S. parauberis that with bouned by one group. The result were S. pauberis that γ-hemolytic chain form cocci and negative reaction of catalase, Multiplex PCR assay were 718 bp amplicon size.