• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1154-1163
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• 2024

Glucosylation is a well-known approach to improve the solubility, pharmacological, and biological properties of flavonoids, making flavonoid glucosides a target for large-scale biosynthesis. However, the low yield of products coupled with the requirement of expensive UDP-sugars limits the application of enzymatic systems for large-scale. C. glutamicum is a Gram-positive and generally regarded as safe (GRAS) bacteria frequently employed for the large-scale production of amino acids and biofuels. Due to the versatility of its cell factory system and its non-endotoxin producing properties, it has become an attractive system for the industrial-scale biosynthesis of alternate products. Here, we explored the cell factory of C. glutamicum for efficient glucosylation of flavonoids using apigenin as a model flavonoid, with the heterologous expression of a promiscuous glycosyltransferase, YdhE from Bacillus licheniformis and the endogenous overexpression of C. glutamicum genes galU1 encoding UDP-glucose pyrophosphorylase and pgm encoding phosphoglucomutase involved in the synthesis of UDP-glucose to create a C. glutamicum cell factory system capable of efficiently glucosylation apigenin with a high yield of glucosides production. Consequently, the production of various apigenin glucosides was controlled under different temperatures yielding almost 4.2 mM of APG1(apigenin-4'-O-β-glucoside) at 25℃, and 0.6 mM of APG2 (apigenin-7-O-β-glucoside), 1.7 mM of APG3 (apigenin-4',7-O-β-diglucoside) and 2.1 mM of APG4 (apigenin- 4',5-O-β-diglucoside) after 40 h of incubation with the supplementation of 5 mM of apigenin and 37℃. The cost-effective developed system could be used to modify a wide range of plant secondary metabolites with increased pharmacokinetic activities on a large scale without the use of expensive UDP-sugars.

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.91-97
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• 1999

In this work, a 1.9-kb region of enterococcal plasmid p703/5 was isolated and the nucleotide sequence analysis of the region was performed. One major open reading frame (ORF) was identified encoding a polypeptide of 28 kDa. Database comparisons suggested that the protein showed some homology with other bacterial RepA proteins. Upstream of the ORF, a potential dnaA box, AT-rich region and 22-bp tandemly repeated sequences (DNA iterons), a feature typical for many replication ori sites, were recognized. Deletion analysis using Exonuclease III and several restriction enzymes indicated that the three elements and the gene product from the ORF were essential for replication and that the minimum unit of DNA required for replication resided on the 1.2-kb AvaII subfragment. Thus, this gene product was referred to as RepA.

• International Journal of Advanced Culture Technology
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• v.5 no.3
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• pp.35-39
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• 2017

The human body is structured as sentence of healing. This study examines how the mechanism of healing works in the human body by the narrative relation of functor and argument. So, we predict the way of extreme healing by literary or human narrative. For this purpose, we analyze the principle that the emotional and semantic arguments are called by the functor set by the sentences containing the fingerprints of mind in Gosijo and the mechanism of healing works extensively. We analyze the process of the transition from the narrative of the literary to the narrative of the human body. Thus, the barcode of the healing, which is made up of the relationship between the functor of the literature and the argument, is transferred to the human body and it is judged that the fingerprint of the human mind is operated through the stage of encoding and re-encoding due to the action potential. In addition, it was predicted that the neurotransmitters such as dopamine and the secretion of hormones would be promoted and the healing level would be increased. In results, we conclude that the function of argument and functor which contains the fingerprint of the mind in the third sound step on the last sentence of Gosijo is transferred to the human body and is especially heavily focused and operate with healing.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.137-140
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• 2014

A gene encoding thermostable pectinase (TmPec) was isolated from hyperthermophilic microorganism, Thermotoga maritima. The open reading frame (ORF) of TmPec gene is 1,104 bp long and encodes 367 amino acid residues with a molecular weight of 40,605 Da. To analyze the enzymatic activity and biochemical properties, the ORF of TmPec gene excluding putative signal sequence of 27 amino acids was introduced into the E. coli expression vector, pRSET-B, and overexpressed in E. coli BL21. Protein concentration of purified recombinant TmPec was 1.1 mg/mL with specific activity of 56 U/mg protein on pectin. The recombinant TmPec showed the highest activity at around $85-95^{\circ}C$, and at around pH 6.5. It was stable at temperature below $85^{\circ}C$. In the presence of $Ca^{2+}$, the activity of recombinant TmPec was increased to 146.3% of normal level. In contrast, $Ba^{2+}$ and Mn2+ showed strong inhibition to the recombinant TmPec.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2765-2768
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• 2014

Flower-like Au nanoparticles, so-called Au nanoflowers (AuNFs), were synthesized by simply adding ascorbic acid to a gold acid solution in the presence of a chitosan biopolymer. The chitosan-entangled AuNFs exhibited strong plasmon absorption in the near-infrared (NIR) wavelength due to the aggregation of primary Au nanoparticles. The chitosan-entangled AuNFs were preferentially adsorbed by Raman-active 2-chlorothiophenol (CTP) molecules, and the CTP-encoded AuNFs (AuNF-CTPs) were subsequently coated with a thin silica layer by a sol-gel reaction with Si alkoxides. The silica-coated AuNFs (AuNF-CTPs@silica) exhibited the distinct Raman signals of adsorbed CTP molecules, as a potential nanoprobe with surface-enhanced Raman scattering (SERS).

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.4
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• pp.318-322
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• 2004

Lactic acid is an environmentally benign organic acid that could be used as a raw material for biodegradable plastics if it can be inexpensively produced by fermentation. Two genes (ldhL and ldhD) encoding the L-(+) and D-(-) lactate dehydrogenases (L-LDH and D-LDH) were cloned from Lactobacillus sp., RKY2, which is a lactic acid hyper-producing bacterium isolated from Kimchi. Open reading frames of ldhL for and ldhD for the L and D-LDH genes were 962 and 998 bp, respectively. Both the L(+)- and D(-)-LDH proteins showed the highest degree of homology with the L- and D-lactate dehydrogenase genes of Lactobacillus plantarum. The conserved residues in the catalytic activity and substrate binding of both LDHs were identified in both enzymes.

• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1585-1590
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• 2002

Rhizomelic chondrodysplasia punctata(RCDP) is a rare autosomal recessive disorder clinically characterized by symmetrical shortening of the proximal limbs, contractures of joints, a typical dysmorphic face, cataracts, and itchyosis. Patients with RCDP can be subdivided into three subgroups based on biochemical analysis and complementation studies. RCDP type I results from mutations in the PEX7 gene encoding the peroxisomal targeting signal type II(PST2) receptors and presents with both a defect in plasmalogen biosynthesis and phytanic acid oxidation. RCDP type II is deficient in the activity of dihydroxyacetonephosphate acyltransferase(DHAP-AT). RCDP type III is deficient in alkyl-dihydroxyacetonephosphate synthase(alkyl-DHAP). We report a case of RCDP type I which was confirmed with biochemical study, fibroblast culture, and gene study.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.213-216
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• 2021

A gene encoding thermostable cellulase A (TmCelA) was isolated from Thermotoga maritima. The open reading frame of TmCelA gene was 774 bp long which predicted to encode 257 amino acid residues with a molecular weight of 29,732 Da. To examine the biochemical properties, the TmCelA was overexpressed in E. coli BL21, and expressed protein was purified. The optimum temperature of recombinant TmCelA was 90-95 ℃, and the optimum pH of recombinant TmCelA was approximately pH 5.0. Recombinant TmCelA was stable at temperature below 90 ℃.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.407-407
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• 2005

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.201.3-201
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• 2003

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