• Molecular & Cellular Toxicology
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• v.5 no.2
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• pp.172-178
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• 2009

Nanoparticles are small-scale substances (<100 nm) with unique properties, complex exposure and health risk implications. Aluminum oxide ($Al_2O_3$) nanoparticles (NP) have been widely used as abrasives, wear-resistant coatings on propeller shafts of ships, to increase the specific impulse per weight of composite propellants used in solid rocket fuel and as drug delivery systems to increase solubility. However, recent studies have shown that nano-sized aluminum (10 nm in diameter) can generate adverse effects, such as pulmonary response. The cytotoxicity and genotoxicity of $Al_2O_3$ NP were investigated using the dye exclusion assay, the comet assay, and the mouse lymphoma thymidine kinase (tk$^{+/-}$) gene mutation assay (MLA). IC$_{20}$ values of $Al_2O_3$ NP in BEAS-2B cells were determined the concentration of 273.44 $\mu$g/mL and 390.63 $\mu$g/mL with and without S-9. However IC$_{20}$ values of $Al_2O_3$ NP were found nontoxic in L5178Y cells both of with and without S-9 fraction. In the comet assay, L5178Y cells and BEAS-2B cells were treated with $Al_2O_3$ NP which significantly increased 2-fold tail moment with and without S-9. Also, the mutant frequencies in the $Al_2O_3$ NP treated L5178Y cells were increased compared to the vehicle controls with S-9. The results of this study indicate that $Al_2O_3$ NP can cause primary DNA damage and cytotoxicity but not mutagenicity in cultured mammalian cells.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.1-6
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• 1992

The aspartame, $\alpha$-L-aspartyl-L-phenylalanine methylester, is an artificial sweetener. Taking advantage of the fact that the aspartame is a derivative of dipeptide, synthesis of aspartame from the artificial polypeptide made by an artificial gene has been attempted. The artificial polypeptide (LAP32), a polymer of tripeptide (aspartyl-phenylalanyl-lysine), was purified from the E. coli cells harboring a recombinant plasmid containing the artificial gene. This polypeptide was then digested with trypsin and carboxypeptidase B to produce dipeptide (Asp-Phe). Using the esterase activity of $\alpha$-chymotrypsin, the dipeptide was directly converted into Asp-Phe methylester in a water-methanol system. When the methanol concentration in reaction mixture was 25%, 50% of dipeptide was converted to the dipeptide methylester without producing any by-products.

• Korean Journal of Radiology
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• v.21 no.6
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• pp.726-735
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• 2020

Objective: Recent innovations in biology are boosting gene and cell therapy, but monitoring the response to these treatments is difficult. The purpose of this study was to find an MRI-reporter gene that can be used to monitor gene or cell therapy and that can be delivered without a viral vector, as viral vector delivery methods can result in long-term complications. Materials and Methods: CMV promoter-human organic anion transporting polypeptide 1B3 (CMV-hOATP1B3) cDNA or CMV-blank DNA (control) was transfected into HEK293 cells using Lipofectamine. OATP1B3 expression was confirmed by western blotting and confocal microscopy. In vitro cell phantoms were made using transfected HEK293 cells cultured in various concentrations of gadoxetic acid for 24 hours, and images of the phantoms were made with a 9.4T micro-MRI. In vivo xenograft tumors were made by implanting HEK293 cells transfected with CMV-hOATP1B3 (n = 4) or CMV-blank (n = 4) in 8-week-old male nude mice, and MRI was performed before and after intravenous injection of gadoxetic acid (1.2 µL/g). Results: Western blot and confocal microscopy after immunofluorescence staining revealed that only CMV-hOATP1B3-transfected HEK293 cells produced abundant OATP1B3, which localized at the cell membrane. OATP1B3 expression levels remained high through the 25th subculture cycle, but decreased substantially by the 50th subculture cycle. MRI of cell phantoms showed that only the CMV-hOATP1B3-transfected cells produced a significant contrast enhancement effect. In vivo MRI of xenograft tumors revealed that only CMV-hOATP1B3-transfected HEK293 tumors demonstrated a T1 contrast effect, which lasted for at least 5 hours. Conclusion: The human endogenous OATP1B3 gene can be non-virally delivered into cells to induce transient OATP1B3 expression, leading to gadoxetic acid-mediated enhancement on MRI. These results indicate that hOATP1B3 can serve as an MRI-reporter gene while minimizing the risk of long-term complications.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.2
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• pp.13-32
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• 2011

Objectives: This study was performed to elucidate the effects of Danchisoyo-san (DS) on cell damage and gene expression in UVB-exposed dermal fibroblast. Methods: To demonstrate the inhibitory effects of DS on aging of the skin, we used human dermal fibroblast(F6) and UVB light(30 mJ/$cm^2$) was used to damage to dermal fibroblast. We measured the nitrite production, LDH release, and gene expression in UVB-irradiated dermal fibroblast to elucidate the actionmechanism of DS. Also, we evaluated the amount of increased PICP, TIMP-1 in dermal fibroblast. PICP, TIMP-1 concentration was measured using EIA kit, and gene expression (MMP-1, procollagen, c-fos, c-jun, NF-kB, Bcl-2, Bcl-xL, iNOS) were determined using real-time PCR. Results: 1. DS inhibited LDH-release, nitrite production in UVB-irradiated dermal fibroblast. 2. DS suppressed the gene expression of MMP-1 in UVB-irradiated dermal fibroblast. 3. DS increased the gene expression of procollagen in UVB-iradiated dermal fibroblast. 4. DS suppressed the gene expression of c-jun, c-fos, NF-kB, iNOS in UVBirradiated dermal fibroblast. 5. DS increased the gene expression of Bcl-2 in UVB-iradiated dermal fibroblast. 6. DS increased the cell proliferation of dermal fibroblast. Conclusions: From the results, we concluded DS increases the cell proliferation and collagen synthesis in dermal fibroblast. So we suggest that DS has the antiwrinkle effects.

• 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.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.299-307
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• 2013

A radish (Raphanus sativus L.) polygalacturonase-inhibiting protein (PGIP) gene was cloned and compared to the PGIP gene (BrPGIP2) from Chinese cabbage (Brassica rapa ssp. pekinensis) in order to gain more information on controlling a disease and improving produce quality. To clone the radish PGIP gene, primers were designed based on conserved sequences of two PGIP genes (BnPGIP1 and BnPGIP2) from rape (B. napus L. ssp. oleifera), Chinese cabbage and Arabidopsis thaliana. PCR cloning was performed with cDNA from the stigma of radish 'Daejinyeoreum' as a template to confirm DNA fragments which were about 600 base pair in size. Sequence analysis revealed 84.1% homology with BrPGIP2 and 70.1% with BnPGIP1. DNA walking was conducted to confirm the open reading frame of 972 bp, and the gene was named RsPGIP1. RsPGIP1 consisting with 323 amino acids (aa) has a high leucine content (54/323) and contains 10 leucine-rich repeat domains, as do most BrPGIPs of Chinese cabbage. The gene expression of RsPGIP1 was induced by abiotic stresses and methyl jasmonate. It showed enrichment in the stigma and the primary root than a leaf. Cloning RsPGIP1 will aid to further apply practices on postharvest quality maintenance and disease control of the root.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.27-28
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• 2014

Beauveria bassiana (Cordycipitaceae, Hypocreales, Ascomycota) is an anamorphic fungus having a potential to be used as a biological control agent because it parasitizes a wide range of arthropod hosts including termites, aphids, beetles and many other insects. A number of bioactive secondary metabolites (SMs) have been isolated from B. bassiana and functionally verified. Among them, beauvericin and bassianolide are cyclic depsipeptides with antibiotic and insecticidal effects belonging to the enniatin family. Non-ribosomal peptide synthetases (NRPSs) play a crucial role in the synthesis of these secondary metabolites. NRPSs are modularly organized multienzyme complexes in which each module is responsible for the elongation of proteinogenic and non-protein amino acids, as well as carboxyl and hydroxyacids. A minimum of three domains are necessary for one NRPS elongation module: an adenylation (A) domain for substrate recognition and activation; a tholation (T) domain that tethers the growing peptide chain and the incoming aminoacyl unit; and a condensation (C) domain to catalyze peptide bond formation. Some of the optional domains include epimerization (E), heterocyclization (Cy) and oxidation (Ox) domains, which may modify the enzyme-bound precursors or intermediates. In the present study, we analyzed genomes of B. bassiana and its allied species in Hypocreales to verify the distribution of NRPS-encoding genes involving biosynthesis of beauvericin and bassianolide, and to unveil the evolutionary processes of the gene clusters. Initially, we retrieved completely or partially assembled genomic sequences of fungal species belonging to Hypocreales from public databases. SM biosynthesizing genes were predicted from the selected genomes using antiSMASH program. Adenylation (A) domains were extracted from the predicted NRPS, NRPS-like and NRPS-PKS hybrid genes, and used them to construct a phylogenetic tree. Based on the preliminary results of SM biosynthetic gene prediction in B. bassiana, we analyzed the conserved gene orders of beauvericin and bassianolide biosynthetic gene clusters among the hypocrealean fungi. Reciprocal best blast hit (RBH) approach was performed to identify the regions orthologous to the biosynthetic gene cluster in the selected fungal genomes. A clear recombination pattern was recognized in the inferred A-domain tree in which A-domains in the 1st and 2nd modules of beauvericin and bassianolide synthetases were grouped in CYCLO and EAS clades, respectively, suggesting that two modules of each synthetase have evolved independently. In addition, inferred topologies were congruent with the species phylogeny of Cordycipitaceae, indicating that the gene fusion event have occurred before the species divergence. Beauvericin and bassianolide synthetases turned out to possess identical domain organization as C-A-T-C-A-NM-T-T-C. We also predicted precursors of beauvericin and bassianolide synthetases based on the extracted signature residues in A-domain core motifs. The result showed that the A-domains in the 1st module of both synthetases select D-2-hydroxyisovalerate (D-Hiv), while A-domains in the 2nd modules specifically activate L-phenylalanine (Phe) in beauvericin synthetase and leucine (Leu) in bassianolide synthetase. antiSMASH ver. 2.0 predicted 15 genes in the beauvericin biosynthetic gene cluster of the B. bassiana genome dispersed across a total length of approximately 50kb. The beauvericin biosynthetic gene cluster contains beauvericin synthetase as well as kivr gene encoding NADPH-dependent ketoisovalerate reductase which is necessary to convert 2-ketoisovalarate to D-Hiv and a gene encoding a putative Gal4-like transcriptional regulator. Our syntenic comparison showed that species in Cordycipitaceae have almost conserved beauvericin biosynthetic gene cluster although the gene order and direction were sometimes variable. It is intriguing that there is no region orthologous to beauvericin synthetase gene in Cordyceps militaris genome. It is likely that beauvericin synthetase was present in common ancestor of Cordycipitaceae but selective gene loss has occurred in several species including C. militaris. Putative bassianolide biosynthetic gene cluster consisted of 16 genes including bassianolide synthetase, cytochrome P450 monooxygenase, and putative Gal4-like transcriptional regulator genes. Our synteny analysis found that only B. bassiana possessed a bassianolide synthetase gene among the studied fungi. This result is consistent with the groupings in A-domain tree in which bassianolide synthetase gene found in B. bassiana was not grouped with NRPS genes predicted in other species. We hypothesized that bassianolide biosynthesizing cluster genes in B. bassiana are possibly acquired by horizontal gene transfer (HGT) from distantly related fungi. The present study showed that B. bassiana is the only species capable of producing both beauvericin and bassianolide. This property led to B. bassiana infect multiple hosts and to be a potential biological control agent against agricultural pests.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.196-201
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• 2012

Microorganisms, having the lower decarboxylase activity, among the isolated strains from $cheonggukjang$ and rice-straw in this study were selected by using biogenic amine (BA) media. The selected strains were identified as $Bacillus$ $subtilis$ HH12, $B.$ $subtilis$ HR254, and $Paenibacillus$ $barcinonensis$ KR97, by using 16S rRNA analysis. PCR analysis showed that the histidine decarboxylase ($hdc$) gene was absent in the HH12, HR254, and KR97 strains. However, PCR analysis showed that the tyrosine decarboxylase ($tdc$) gene was present in the HH12, HR254, and KR97 strains. Quantitative analysis of the selected strains by using high-performance liquid chromatography showed that histamine was absent in the HH12, HR254, and KR97 strains. However, these 3 strains showed tyramine concentrations of 6.09, 3.68, and 6.30 mg/L, respectively. These strains produced lower concentrations of amines (approximately 7.9, 0, and 9.3% amines in the HH12, HR254, and KR97 strains, respectively) than the $B.$ $subtilis$ MC138 strain, which showed the higher protease activity.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.36-42
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• 2013

The average twin lambing rate of Bayanbulak sheep is 2% to 3%. However, a flock of sheep with a close genetic relationship and an average of 2 to 3 lambs per birth has been found recently. To determine the major genes controlling the prolificacy of the flock in the present study, the flock was designated A while 100 normal Bayanbulak sheep were randomly selected to comprise the control flock B. Ligase detection reaction method was applied to detect and analyze the 10 mutational loci of the 3 candidate prolificacy genes including bone morphogenetic protein type I receptors, bone morphogenetic protein 15, and growth differentiation factor 9. The 10 mutational loci are as follows: FecB locus of the BMPR-IB gene; $FecX^I$, $FecX^B$, $FecX^L$, $FecX^H$, $FecX^G$, and $FecX^R$ of the BMP15 gene; and G1, G8, and FecTT of the GDF9 gene. Two mutations including BMPR-IB/FecB and GDF9/G1 were found in Bayanbulak sheep. Independence test results of the two flocks demonstrate that the FecB locus has a significant effect on the lambing number of Bayanbulak sheep. However, the mutation frequency of the G1 locus in GDF9 is very low. Independence test results demonstrate that the GDF9 locus does not have a significant impact on the lambing performance of Bayanbulak sheep. Among the 10 detected loci, BMPR-IB/FecB is the major gene that influences the high lambing rate of Bayanbulak sheep.

• Journal of Life Science
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• v.16 no.5
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• pp.828-833
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• 2006

Maize (Zea mays L.) pistil cell death and stamen cell arrest are pivotal process on the sex determination, which diverges from bisexual state of floral meristem to unisexual state in staminate or pistillate floret. We investigated the temporal and spatial distribution of cell cycle gene expression during maize sex determination. The positive regulatory genes of cell cycle, cyclin A, cyclin B, cyclin dependent kinase (CDK) and Mad2 were highly expressed in the developing pistil and stamen but the expression was disappeared in the dying pistil and arresting stamens. In contrast, the negative regulatory genes of cell cycle, Wee1 and CDK inhibitor (CKI) were expressed in the arresting stamens in the wild-type ear and tasselseed2 mutant tassel, however, these genes were not detected in dying pistil although the cyclin B gene expression was disappeared. These results suggest that both the pistil cell death and stamen cell arrest process in maize sex determination are involved in cell cycle regulation, but the different expression patterns of negative regulatory cell cycle genes in the arresting stamens and aborting pistils suggest that the two processes may have distinctive modes of action.