• Journal of Ginseng Research
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• v.10 no.2
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• pp.200-208
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• 1986

It was attempted in this study to investigate the effect of ginseng saponin on several glycolytic enzymes of yeast cell and the following results were obtained. The amount of $CO_2$formed during the incubation of yeast cells in medium containing saponin fraction of Panax ginseng C.A. Meyer was greater than that of control cells and found that the $CO_2$ formation was greatest when the cells were grown in the medium containing 10$^{-3}$% of the saponin fraction, at which the uptake of inorganic phosphate and glucose consumption were also increased. Radioactivity study of several glycolytic intermediates of yeast cells cultured in the medium containing [U-$^{14}$C]-glucose showed that the radioactivity of fructose 6-phosphate of test cells was as much as 1.6times that of control group. On the other hand, the radioactivity of pyruvate of test cells was considerably decreased compared to control. Investigation of the effect of ginseng saponin on yeast hexokinase, phosphoglucose isomers, pyruvate kinase and perverted decarboxylase in vitro showed that the maximum activities of the above enzymes were observed when the concentration of ginseng saponin was 10-$^{-5}$% in the reaction mixture. It seemed that the ginseng saponin stimulated both glycolytic enzymes such as hexokinase, phosphoglucose isomers and perverted decarboxylase significantly.

• Bulletin of the Korean Chemical Society
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• v.24 no.10
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• pp.1465-1469
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• 2003

A neutral ligand is synthesized and studied for the binding properties with anions by electrochemical methods. The binding of 1,8-bis[(N'-phenylureido)ethyloxy]anthraquinone (BPUA) with $H_2PO_4^-$ makes cathodic shift of its electrochemical potentials and red shift of absorption band. This novel neutral anion receptor BPUA binds anions through hydrogen bonding and show high selectivity with $H_2PO_4^-$ over $CH_3CO_2^-,CI^-,{\;}and{\;}HSO_4^-$. The selecivity of H_2PO_4^-$ over $CH_3CO_2^-,CI^-,{\;}and{\;}HSO_4^-$ may be attributed to the stronger hydrogen bonding with urea moiety and also with anthraquinone moiety of BPUA receptor, and also the higher complementarity of the cavity of BPUA for tetrahedral H_2PO_4^-$.

• BMB Reports
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• v.42 no.8
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• pp.523-528
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• 2009

Phosphomannose isomerase (PMI) catalyzes the interconversion of fructose-6-phosphate and mannose-6-phosphate in the extracellular polysaccharide (EPS) synthesis pathway. The gene encoding PMI in Sphingomonas chungbukensis DJ77 was cloned and expressed in E. coli. The pmi gene is 1,410 nucleotides long and the deduced amino acid sequence shares high homology with other bifunctional proteins that possess both PMI and GDP-mannose pyrophosphorylase (GMP) activities. The sequence analysis of PMI revealed two domains with three conserved motifs: a GMP domain at the N-terminus and a PMI domain at the C-terminus. Enzyme assays using the PMI protein confirmed its bifunctional activity. Both activities required divalent metal ions such as $Co^{2+}$, $Ca^{2+}$, $Mg^{2+}$, $Ni^{2+}$ or $Zn^{2+}$. Of these ions, $Co^{2+}$ was found to be the most effective activator of PMI. GDP-D-mannose was found to inhibit the PMI activity, suggesting feedback regulation of this pathway.

• Journal of Microbiology and Biotechnology
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• v.31 no.10
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• pp.1393-1400
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• 2021

Acetone-butanol-ethanol (ABE) fermentation by the anaerobic bacterium Clostridium acetobutylicum has been considered a promising process of industrial biofuel production. Phosphotransbutyrylase (phosphate butyryltransferase, PTB) plays a crucial role in butyrate metabolism by catalyzing the reversible conversion of butyryl-CoA into butyryl phosphate. Here, we report the crystal structure of PTB from the Clostridial host for ABE fermentation, C. acetobutylicum, (CaPTB) at a 2.9 Å resolution. The overall structure of the CaPTB monomer is quite similar to those of other acyltransferases, with some regional structural differences. The monomeric structure of CaPTB consists of two distinct domains, the N- and C-terminal domains. The active site cleft was formed at the interface between the two domains. Interestingly, the crystal structure of CaPTB contained eight molecules per asymmetric unit, forming an octamer, and the size-exclusion chromatography experiment also suggested that the enzyme exists as an octamer in solution. The structural analysis of CaPTB identifies the substrate binding mode of the enzyme and comparisons with other acyltransferase structures lead us to speculate that the enzyme undergoes a conformational change upon binding of its substrate.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.418-424
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• 2018

${\text\tiny{D}}-Allose$ is a potential medical sugar because it has anticancer, antihypertensive, antiinflammatory, antioxidative, and immunosuppressant activities. Allose production from fructose as a cheap substrate was performed by a one-pot reaction using Flavonifractor plautii ${\text\tiny{D}}-allulose$ 3-epimerase (FP-DAE) and Clostridium thermocellum ribose 5-phosphate isomerase (CT-RPI). The optimal reaction conditions for allose production were pH 7.5, $60^{\circ}C$, 0.1 g/l FP-DAE, 12 g/l CT-RPI, and 600 g/l fructose in the presence of 1 mM $Co^{2+}$. Under these optimized conditions, FP-DAE and CT-RPI produced 79 g/l allose for 2 h, with a conversion yield of 13%. This is the first biotransformation of fructose to allose by a two-enzyme system. The production of allose by a one-pot reaction using FP-DAE and CT-RPI was 1.3-fold higher than that by a two-step reaction using the two enzymes.

• IMMUNE NETWORK
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• v.14 no.2
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• pp.100-106
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• 2014

Infection with invasive Shigella species results in intestinal inflammation in humans but no symptoms in adult mice. To investigate why adult mice are resistant to invasive shigellae, 6~8-week-old mice were infected orally with S. flexneri 5a. Shigellae successfully colonized the small and large intestines. Mild cell death was seen but no inflammation. The infected bacteria were cleared 24 hours later. Microarray analysis of infected intestinal tissue showed that several genes that are involved with the sphingosine-1-phosphate (S1P) signaling pathway, a lipid mediator which mediates immune responses, were altered significantly. Shigella infection of a human intestinal cell line modulated host S1P-related genes to reduce S1P levels. In addition, co-administration of S1P with shigellae could induce inflammatory responses in the gut. Here we propose that Shigella species have evasion mechanisms that dampen host inflammatory responses by lowering host S1P levels in the gut of adult mice.

• Journal of Plant Biology
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• v.34 no.4
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• pp.303-309
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• 1991

Limitation of photosynthesis in detached Chinese cabbage (Brassica campestris L.) leaves was induced by feeding of mannose (25 mM) for 12 h in the light, and changes in the basic thylakoid functions under this condition were investigated. The acid soluble phosphate contend and CO2 uptake rate was decreased by 66% and 67%, respectively. However, the starch content was increased by 24% compared to those of controls. From the fast induction curves of chlorophyll fluorescence, dark level fluorescence (Fo) slightly increased while intermediate plateau fluorescence level (FI) to peak level fluorescence (Fp) transient was significantly decreased with a slight decrease in the Fo-to-FI transient. This data means that reduction of secondary electron acceptor of PSII (QB) might be more severely inhibited than that of primary electron acceptor of PSII (QA) by decrease in phosphate level. The strong decline of (Fv)m//Fm ratio suggests that efficiency of excitation energy capture by PSII was decreased markedly. The quenching of Fo (qO), an indicator of state transition, was also occurred over the slow induction kinetics of chlorophyll fluorescence. From quenching analysis, fluorescence was dominantly quenched by nonphotochemical quenchings (qE+qT). These results showed that the capture and transfer efficiency of excitation energy to PSII reaction center in thylakoid was decreased with the decline of leaf phosphate level, and that the state transition was occurred during the induction of photosynthesis under these conditions.

• Korean Journal of Food Science and Technology
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• v.17 no.4
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• pp.245-247
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• 1985

The effect of a polyphosphate having $P_2O_5$ content of 67% on the firming rate of nonwaxy (Akibare and Milyang 30) and waxy cooked rice stored at room temperature was investigated. The phosphate retarded the firming rate of Akibare and Milyang 30 by 14.0 and 27:00, respectively. The phosphate reduced the starch components available for crystallization of cooked nonwaxy rice. The phosphate exerted no effect on the firming rate of cooked waxy rice.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.4
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• pp.291-297
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• 2019

Phosphorus is a vital resource for sustaining agriculture and nutrition, but a limited non-renewable resource. Thus, the recovery of phosphorus from waste activated sludge(WAS) was attempted by microwave heating and magnesium ammonium phosphorus(MAP) crystallization. Polyphosphate-accumulating organisms(PAOs) in WAS release phosphate from the cell when they are exposed to high temperature environments. Microwave heating caused phosphorus and ammonia to release from WAS. The amount was increased with increasing temperature, showing that 88.5% of polyphosphate present in the cells were released in the form of phosphate at $80^{\circ}C$. A similar result was also observed in the release of ammonia. On the other hand, both phosphorus and ammonia were crystallized with magnesium, and then was harvested as MAP. Phosphorus recovery rate reached almost 97.8%, but the ammonia was about 13.4%. These results cleary indicate that phosphorus could be recovered from WAS using a physiological trait of PAOs. Heavy metal analyses also show that the MAP crystal is useful and safe as a phosphorus fertilizer.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.31 no.2
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• pp.92-95
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• 2020

Tracheal granuloma, the most commonly reported sequela of pediatric tracheotomy. A variety of techniques are available for the management of tracheal granuloma. Potassium-titanyl-phosphate (KTP) laser has been previously established as an acceptable technique for removal of laryngeal surgery, which emits a green light with a wave length of 532 nm, which is well-absorbed by hemoglobin and can coagulate and vaporize tissue. The ability to deliver laser energy through a flexible glass fiber makes the technique convenient for use with a rigid bronchoscope, overcoming problems with intraluminal access encountered with earlier attempts at CO2 laser therapy for this problem. Another advantage of KTP laser is the avoidance of the risks and morbidity associated with an open procedure. We report our surgical technique KTP laser in the management of tracheal granuloma removal into the tracheostomy site. KTP laser is good tool for management of tracheal granuloma with low incidence of complications.