• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.141-146
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• 2000

Glycosidase activities were tested from the grape berries, Vitis labruscana B. Takasumi. Among various glycosidases, $\alpha$-D-galactosidase was found to be the most active in the flesh and other glycosidases were considerably active in the order of the following: $\alpha$-D-mannosidase>$\alpha$-D-glucosidase>$\beta$-D-glucosidase>$\beta$-D-galactosidase. In the seeds, $\alpha$-D-glucosidase activity was the highest and other glycosidases such as $\alpha$-D-galactosidase, $\beta$-D-glucosidase, and $\beta$-D-galactosidase were still significantly active. The $\alpha$-D-galactosidase in the grape flesh was purified over 83-folds through salting-out with $(NH_4)_2SO_4$ and a series of chromatographies employing Sephadex G-50, Octyl-Sepharose, Q-Sepha- rose, and Biogel P-100. The enzyme was a monomer of 45 kDs as determined through SDS-PAGE and Sephacryl S-200 chromatography. The purified enzyme showed a preference of $\alpha$-D-galactose to $\beta$-D-galactose as a substrate about 5.4 times. Sulfhydryl specific reagents such as N-ethylmaleimide and iodoacetamide significantly inhibited the enzyme activity to the extents of 48 and 52% of its initial activity, respectively. The optimumpH range of $\alpha$-D-galactosidase was around 6.5-7.0. The enzyme activity increased by 46% in the presence of 1mM $Fe^{2+}$.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.606-607
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• 2005

• The Plant Pathology Journal
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• v.24 no.1
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• pp.58-62
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• 2008

Utilization of carbon sources by Bacillus cereus D324, a biological control agent, and Pythium species, which causes rice seedling disease, was studied with the objective of increasing the efficacy of biological control by providing the biological control agent with specific beneficial carbon sources. D-galactose, D-sorbitol, and D-mannitol were poor carbon sources for Pythium spp. growth but were good for B. cereus D324 growth. Growth in a growth chamber of rice seeds coated with B. cereus D324 amended with specific carbon sources, such as D-galactose and D-sorbitol, showed significantly enhanced seedling emergence compared to seeds coated only with B. cereus D324. Field trials showed that both seedling emergence and yield increased, when the above specific carbon sources were added to B. cereus D324 in seed coating formulations. This result indicated that amending seed coating formulations with specific carbon sources could significantly increase seedling emergence and yield in the field.

• Archives of Pharmacal Research
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• v.23 no.2
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• pp.182-186
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• 2000

Chondroitin sulfates proteoglycans were isolated from human placenta. For the identification of enzymatic digestion products of isolated proteoglycan, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitin ABC and chondroitin B lyase, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-($\beta$-D-gluco-4-enepyranosyluronic acid)-D-galactose ($\delta$Di-OS), 2-acetamide-2-deoxy-3-O-($\beta$-D-gluco-4-enepyranosyluronic acid)-6-O-su lfo-D-galactose ($\delta$Di-6S) and 2-acetamide-2-deoxy-3-O-($\beta$-D-gl uco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose ($\delta$Di-4S) were produced from the human placenta proteoglycan. The anticoagulant activity of chondroitin sulfate proteoglycan was evaluated by activated partial thromboplastin time (aPTT) assay and thrombin time (TT) assay. The clotting times of aPTT and TT were increased from 72 to 144 sec and 19 to 27 sec, respectively. The Immune-modulating activity of chondroitin sulfate proteoglycan was examined by cell proliferation assay and these results suggest that it may play a role in suppression of the function of immune-related cells.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1919-1926
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• 2020

CRISPR interference (CRISPRi) has been developed as a transcriptional control tool by inactivating the DNA cleavage ability of Cas9 nucleases to produce dCas9 (deactivated Cas9), and leaving dCas9 the ability to specifically bind to the target DNA sequence. CRISPR/Cas9 technology has limitations in designing target-specific single-guide RNA (sgRNA) due to the dependence of protospacer adjacent motif (PAM) (5'-NGG) for binding target DNAs. Reportedly, Cas9-NG recognizing 5'-NG as the PAM sequence has been constructed by removing the dependence on the last base G of PAM through protein engineering of Cas9. In this study, a dCas9-NG protein was engineered by introducing two active site mutations in Cas9-NG, and its ability to regulate transcription was evaluated in the gal promoter in E. coli. Analysis of cell growth rate, D-galactose consumption rate, and gal transcripts confirmed that dCas9-NG can completely repress the promoter by recognizing DNA targets with PAM of 5'-NGG, NGA, NGC, NGT, and NAG. Our study showed possible PAM sequences for dCas9-NG and provided information on target-specific sgRNA design for regulation of both gene expression and cellular metabolism.

• YAKHAK HOEJI
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• v.43 no.4
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• pp.423-428
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• 1999

Two polysaccharides, ACP-UMP and ACP-ULF, were purified from the aerial part of Artemisia capillaris by anion-exchange chromatography, ultrafiltration, and gel filtration chromatography. The polysaccharides appeared to be homogenious from the results of HPLC. The molecular weights of ACP-UMF and ACP-ULF were estimated to be 16305.92 D and 3292.26 D, respectively, by MALDI-TOF MS. The sugar compositions were determined by GC to be arabinose 10.05%, xylose 1.67%, mannose 5.45G, galactose 39.06%, glucose 15.43% for ACP-UMF and arabinose 11.60%, xylose 11.15%, mannose 6.37% galactose 32.47%, glucose 18.35% for ACP-ULF. A polysaccharide, SP-M was determined to be 2462.52 D by MALDI-TOF MS. SP-M consisted mainly of rhamnose 36.49%, arabinose 29.00%, and glucose 19.38%. Incubation of CCl4-intoxicated hepatocytes with ACP-UMF reduced the levels of glutamic pyruvic transaminase (GPT) and cellular malondialdehyde (MDA) to 62.8% and 23.8%. ACP-ULF also reduced the levels of GPT and MDA to 46.1% and 38.1% and 26.3%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.8 no.1
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• pp.63-70
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• 1979

One species of Rhodophyceae namely Eucheuma cottonii from the coast of Philippine was analyzed with respect to the content of carrageenan and such chemical characteristics as the content of sulphate and 3,6-anhydro-D-galactose and its solubility in potassium chloride solution. In addition, the same chemical properties were tested in the fractions separated by the different concentrations of potassium chloride. In comparison of the results of carrageenan in Eucheuma cottonii samples from Philippine and Chondrus ocellatus samples from Korea, carrageenan content in Eucheuma cottonii was higher than that of Chondrus ocellatus. Both samples showed more than forty-five percent carrageenan content. The Eucheuma cottonii carrageenan showed a higher 3,6-anhydro-D-galactose than the Chondrus ocellatus carrageenan. The sulphate content was higher in Chondrus ocellatus than Eucheuma cottonii. In fractionation of carrageenan by the solubility methods using potassium chloride solution, the yield of Eucheuma cottonii was highest in fraction I, fraction III was next and fraction II was the lowest.

• Korean Journal of Microbiology
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• v.22 no.2
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• pp.77-84
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• 1984

This examined some conditions for the induction of ${\beta}$-D-galactosidase synthesis in Candida kefyr CBS 834. The optimal pH, temperature, and inoculum size either for growth or${\beta}$-D-galactosidase synthesis were 5.5, $30^{\circ}C$ and above 0.2 at A610nm, respectively. Enzyme activity began to increase at 2h after the addition of inducer, and continued to increase linearly up to $2{\sim}3h$ before reaching stationary phase, and thereafter its activity was decreased. ${\beta}$-D-galactosidase was induced either by lactose or galactose but not either by glucose or ethanol. The greater activity of ${\beta}$-D-galactosidase on galactose than on lactose indicated that the former might be natural inducer for ${\beta}$-D-galactosidase synthesis. The rate of its induction as a function of lactose concentration showed that enzyme activity increased linearly above 4mM, while it was very low below that. Glucose represed the induction of ${\beta}$-D-galactosidase, and the period of adaptation to inducer from other carbon sources was relatively short.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.72-80
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• 1997

To elucidate food value and medicinal effect of sea cucumbers, sugar composition of those gly-coprotein and chondroitin sulfate was studied. The contents of sulfate esters in sea cucumbers were 1.21%(blue), 0.90%(red) and 1.19%(black). Predominant carbohydrates were identified as fucose, glucose, D-mannuronic acid and N-acetylglucosamine, and those amount was more than 80% to total carbo-hydrate, while the minor sugar composition was ribose, mannose, galactose, N-acetylgalactosamine and D-glucuronic acid. Also, the major carbohydrate moiety of glycoproteins of sea cucumbers was revealed as fucose, mannose, N-acetylglucosamine, glucose and ribose, and those amount was more than 86% to total carbohydrate. Galactose, N-acetylgalactosamine, D-glucuronic acid and mannuronic acid were minor carbohydrate moiety. The contents of sulfate esters in glycoproteins were 0.96% for blue sea cucumber, 1.15% for red sea cucumber and 1.13% for black sea cucumber, while those in chondroitin sulfates were 3.52%(blue), 3.60%(red) and 3.72%(black). The carbohydrate moiety of chondroitin sulfate was identified as N-acetylgalactosamine (73~ 87%), fucose (7~15%) and D-glucuronic acid(5~12%). As the base on the IR spectrum of strong absorption appeared in 1240$cm^{-1}$ / for stretching vibrations in S=0 group and weak absorptions in 850$cm^{-1}$ / and 820$cm^{-1}$ /for stretching vibrations in C-0-S group, chondroitin sulfates had sulfate group which was bound to $C_4$in fucose.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.290-295
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• 2009

Red-algae agar, consisting of D-galactose and 3, 6-anhydro-L-galactose, is usable for bio-ethanol production if hydrolyzed to monomer unit. The objective of this study is to produce bio-ethanol from agar using the heat and acid-treatment. Bio-ethanol was produced by Saccharomyces cerevisiae KCCM1129 strains using agar-pretreatment. The optimal condition for reducing sugar conversion by agar was found to be 15 min reaction at a HCl concentration of 0.1 N and $120^{\circ}C$. The optimum concentration for maximum cell growth was 0.1 N NaCl (17.88 g/L). Over 0.1 N NaCl, the cell growth decreased to 6.78~10.76 g/L. At 16% agar concentration, the ethanol production obtained by optimum pretreatment was found to be 10.16 g/L.