• Molecules and Cells
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• v.40 no.9
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• pp.607-612
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• 2017

When mammalian cells and animals face a variety of internal or external stresses, they need to make homeostatic changes so as to cope with various stresses. To this end, mammalian cells are equipped with two critical stress responses, autophagy and cellular senescence. Autophagy and cellular senescence share a number of stimuli including telomere shortening, DNA damage, oncogenic stress and oxidative stress, suggesting their intimate relationship. Autophagy is originally thought to suppress cellular senescence by removing damaged macromolecules or organelles, yet recent studies also indicated that autophagy promotes cellular senescence by facilitating the synthesis of senescence-associated secretory proteins. These seemingly opposite roles of autophagy may reflect a complex picture of autophagic regulation on cellular senescence, including different types of autophagy or a unique spatiotemporal activation of autophagy. Thus, a better understanding of autophagy process will lead us to not only elucidate the conundrum how autophagy plays dual roles in the regulation of cellular senescence but also helps the development of new therapeutic strategies for many human diseases associated with cellular senescence. We address the pro-senescence and anti-senescence roles of autophagy while focusing on the potential mechanistic aspects of this complex relationship between autophagy and cellular senescence.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.402-407
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• 2010

Zerovalent iron (ZVI) is one of the most commonly used metallic reducing agents for the treatment of toxic contaminants in wastewater. Traditional ZVIs are less effective than nanoscale ZVI (nZVI) due to prolonged reaction time. However, the reactivity can be significantly increased by reducing the size of ZVI particles to nanoscale. In this study, nZVI particles were synthesized under laboratory condition and their efficiency in removing hexavalent chromium (Cr(VI)) from aqueous solutions were compared with commercially available ZVI particles. The results showed that the synthesized nZVI particles (SnZVI) reduced >99% of Cr(VI) at the application rate of 0.2% (w/v), while commercial nZVI (CnZVI) particles resulted in 59.6% removal of Cr(VI) at the same application rate. Scanning electron micrographs (SEM) and energy dispersive spectra (EDS) of the nZVI particles revealed the formation of Fe-Cr hydroxide complex after reaction. Overall, the SnZVI particles can be used in treating chromium contaminated wastewater.

• Molecules and Cells
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• v.40 no.5
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• pp.315-321
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• 2017

The inositol polyphosphates are a group of multifunctional signaling metabolites whose synthesis is catalyzed by a family of inositol kinases that are evolutionarily conserved from yeast to humans. Inositol polyphosphate multikinase (IPMK) was first identified as a subunit of the arginine-responsive transcription complex in budding yeast. In addition to its role in the production of inositol tetrakis- and pentakisphosphates ($IP_4$ and $IP_5$), IPMK also exhibits phosphatidylinositol 3-kinase (PI3-kinase) activity. Through its PI3-kinase activity, IPMK activates Akt/PKB and its downstream signaling pathways. IPMK also regulates several protein targets non-catalytically via protein-protein interactions. These non-catalytic targets include cytosolic signaling factors and transcription factors in the nucleus. In this review, we highlight the many known functions of mammalian IPMK in controlling cellular signaling networks and discuss future challenges related to clarifying the unknown roles IPMK plays in physiology and disease.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.667-686
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• 2019

Streptomyces are attractive microbial cell factories that have industrial capability to produce a wide array of bioactive secondary metabolites. However, the genetic potential of the Streptomyces species has not been fully utilized because most of their secondary metabolite biosynthetic gene clusters (SM-BGCs) are silent under laboratory culture conditions. In an effort to activate SM-BGCs encoded in Streptomyces genomes, synthetic biology has emerged as a robust strategy to understand, design, and engineer the biosynthetic capability of Streptomyces secondary metabolites. In this regard, diverse synthetic biology tools have been developed for Streptomyces species with technical advances in DNA synthesis, sequencing, and editing. Here, we review recent progress in the development of synthetic biology tools for the production of novel secondary metabolites in Streptomyces, including genomic elements and genome engineering tools for Streptomyces, the heterologous gene expression strategy of designed biosynthetic gene clusters in the Streptomyces chassis strain, and future directions to expand diversity of novel secondary metabolites.

• KSBB Journal
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• v.23 no.5
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• pp.449-451
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• 2008

Ceramide has become a widely used ingredient in cosmetic and pharmaceutical industries, however, only a few yeast strains were investigated for the synthesis of ceramide and the concentration was very low. Ceramide is not only a core intermediate of sphingolipids but also an important modulator of many cellular events including apoptosis, cell cycle arrest, senescence, differentiation, and stress responses. In this study S.cerevisiae was grown in a batch culture and the cellular content of ceramide was measured at different growth phases. The ceramide content was highest at stationary phase and 2.01 mg ceramide/g cell was obtained.

• The Plant Pathology Journal
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• v.18 no.1
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• pp.1-5
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• 2002

The availability of nucleotide sequences of the coat protein gene of Potato leafroll virus (PLRV) permitted the construction of DNA primers that were utilized for cDNA synthesis. Polymerase chain reaction (PCR) products of a 487 bp. and approximately 500 bp DNA fragments were amplified from nucleic acid extracts of PLRV-infected tissue and strawberry mild yellow-edge (SMYE) diseased strawberry tissue, respectively. The amplified DNA fragments were further differentiated by hybridization analysis with a CDNA probe for the coat protein gene of PLRV and restriction fragment length polymorphism (RFLP) analysis. These results suggest that a luteovirus is associated with the SMYE disease.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1299-1303
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• 2005

Human articular chondrocytes (HAC) were cultivated as a monolayer in a serum-free medium for primary culture (SFM-P). An optimized SFM-P provides $95\%$ proliferation rate of that obtainable from primary and secondary chondrocyte cultures grown in a control medium with serum. The gradual decrease in the amounts of synthesized glycosaminoglycan and type II collagen was improved by coating the culture dishes with type IV collagen and fibronectin. A significant improvement in the expression of type II collagen and aggrecan mRNA could be achieved. In addition, the monolayer cultures showed better synthesis of the extracellular matrices than alginate-bead cultures in SFM-P.

• CELLMED
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• v.6 no.4
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• pp.22.1-22.19
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• 2016

The biologically active compounds derived from different natural organisms such as animals, plants, and microorganisms like algae, fungi, bacteria and merine organisms. These natural compounds possess diverse biological activities like anthelmintic, antibacterial, antifungal, antimalarial, antiprotozoal, antituberculosis, and antiviral activities. These biological active compounds were acted by variety of molecular targets and thus may potentially contribute to several pharmacological classes. The synthesis of natural products and their analogues provides effect of structural modifications on the parent compounds which may be useful in the discovery of potential new drug molecules with different biological activities. Natural organisms have developed complex chemical defense systems by repelling or killing predators, such as insects, microorganisms, animals etc. These defense systems have the ability to produce large numbers of diverse compounds which can be used as new drugs. Thus, research on natural products for novel therapeutic agents with broad spectrum activities and will continue to provide important new drug molecules.

• Applied Biological Chemistry
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• v.29 no.4
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• pp.399-406
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• 1986

2-Acylaminobenzothiazole derivatives were synthesized from 2-aminobenzothiazole and acylchloride. Benzothiazolylurea derivatives were syntesized from 2-minobenzothiazole and phenylisocyanate. The products were identified by UV, IR, $^1H-NMR$, $^{13}C-NMR$ spectra with 2-acetamidobenzothiazole(I), 2-propionamidobenzothiazole(II), 2-butamidobenzothiazole(III), 2-benzamidobenzothiazole(IV). The compounds were tested for their phytotoxicity on the germination and seedling growth of rice, radish and green pea plants, It was found that treatment of 500ppm concentration each of 2-acetamidobentothiazole, 2-propionarmidobenzothiazole and 2-butamidobenzothiazole strongly inhibited of seedling growth of the radish and green pea.

• YAKHAK HOEJI
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• v.34 no.5
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• pp.296-301
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• 1990

Irradiation of the berberinephenolbetaine in a stream of argon produced the 8,14-cycloberberines [1]. On treatment with ethylchloroformate $C_8-N$ bond cleavage of the compound [1] occurred, accompanied with dehydrochlorination to give 7-ethylcarboxyisoquinoline [3], and the product [3] treated with strong alkali solution to give the 13-oxonorotensane [4] in 64% yield. Irradiation of the compound [4] converted easily to dihydro-8H-dibenzo[a, g] quinolizine-8-one [5]. and then the compound [5] was treated with methyliodide to give the 8-oxo-quinolizinium methiode. The intermediate colume chromatography on IRA-400 afforded the benzo[c, g]azecine-5-one[6] in 63% yield. The results of biological activities for these compounds are also presented.