• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.283-286
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• 2008

The methylenetetrahydrofolate dehydrogenase/cyclohydrolase (MTHFDC) from the thermoacidophilic archaeon Thermoplasma acidophilum is a 30.6kDa molecular-mass enzyme that sequentially catalyzes the conversion of formyltetrahydrofollate to methylenetetrahydrofolate, with a preference for NADP as a cofactor, rather than NAD. In order to elucidate the functional and structural features of MTHFDC from archaeons at a molecular level, it was overexpressed in Escherichia coli and crystallized in the presence of its cofactor, NADP, at 295K using polyethylene glycol (PEG) 4000 as a precipitant. The crystal is a member of the monoclinic space group $P2_1$, with the following unit cell parameters: $a=66.333{\AA},\;b=52.868{\AA},\;c=86.099{\AA},\;and\;{\beta}=97.570^{\circ}$, and diffracts to a resolution of at least $2.40{\AA}$ at the synchrotron. Assuming a dimer in the crystallographic asymmetric unit, the calculated Matthews parameter $(V_M)\;was\;2.44{\AA}^3/Da$ and the solvent content was 49.7%.

• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.295-298
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• 2008

Creatine kinase (CK; E.C. 2.7.3.2) is an important enzyme that catalyzes the reversible transfer of a phosphoryl group from ATP to creatine in energy homeostasis. The brain-type cytosolic isoform of creatine kinase (BB-CK), which is found mainly in the brain and retina, is a key enzyme in brain energy metabolism, because high-energy phosphates are transfered through the creatine kinase/phosphocreatine shuttle system. The recombinant human BB-CK protein was overexpressed as a soluble form in Escherichia coli and crystallized at $22^{\circ}C$ using PEG 4000 as a precipitant. Native X-ray diffraction data were collected to $2.2{\AA}$ resolution using synchrotron radiation. The crystals belonged to the tetragonal space group $P4_32_12$, with cell parameters of a=b=97.963, $c=164.312{\AA},\;and\;{\alpha}={\beta}={\gamma}=90^{\circ}$. The asymmetric unit contained two molecules of CK, giving a crystal volume per protein mass $(V_m)$ of $1.80{\AA}^3\;Da^{-1}$ and a solvent content of 31.6%.

• Current Research on Agriculture and Life Sciences
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• 제31권2호
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• pp.75-82
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• 2013

Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.

• Bulletin of the Korean Chemical Society
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• 제27권4호
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• pp.568-572
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• 2006

To study the effect of sequence on DNA structure, the two decamer crystal structures one alternating,d(GTACGCGTAC), and the other non-alternating, d(GGCCGCGGCC), were solved. Crystals of both decamers belong to the hexagonal space group $P6_122$, with one strand in the asymmetric unit. The unit cell constants of the alternating decamer are a = b = 39.26 $\AA$, c = 77.70 $\AA$. The structure was refined with 1,828 reflections from 8.0 to 2.0 Aresolution to an R value of 21.3% with all DNA atoms and 63 water molecules. The isomorphous non-alternating decamer had unit cell dimensions of a = b = 39.05 $\AA$, c = 82.15 $\AA$. The structure was refined with 2,423 reflections from 8.0 to 2.0 $\AA$ resolution to a final R value of 22.2% for all DNA atoms and 65 water molecules. Although the average helical parameters of the decamers are typical of A-DNAs, there are some minor differences between them. The helical twist, rise, x-displacement, inclination and roll alternate in the alternating decamer, but do not in the non-alternating decamer. The backbone conformations in both structures show some differences; the residue G(7) of the alternating decamer is trans for $\alpha$ and $\gamma$ while the trans conformations are observed at the residue G(8) of the non-alternating decamer.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.227-232
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• 2012

Galectins are generally believed to be potential candidates for use in the development of novel antiinflammatory agents or as selective modulators of the immune response. In particular, galectin-9 exhibits some of the extracellular functions, including cell aggregation, adhesion, chemoattraction, activation, and apoptosis. Tl-galectin (Tl-gal, galectin-9 homologue gene) was isolated from an adult worm of the Toxascaris leonina. The full-length Tl-gal gene, which was incorporated into pET-28a, was overexpressed in E. coli and purified by nickel affinity and gel filtration chromatographies. The purified Tl-gal was crystallized using the hangingdrop vapor-diffusion method. The crystal belonged to the tetragonal space group $P4_1$, with unit-cell parameters of a = b = $75.7\AA$ and c = $248.4\AA$. The crystals were obtained at $20^{\circ}C$ and diffracted to a resolution of $3.0\AA$. The asymmetric unit contained four molecules of Tl-gal, which gave a crystal volume per protein mass (Vm) of $2.8\AA^3Da^{-1}$ and a solvent content of 54.1%.

• 한국자원식물학회지
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• 제19권3호
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• pp.418-421
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• 2006

In this study, we surveyed the influence of IOA (iodoacetamide) and media upon protoplast fusion for the efficient production of the somatic hybrid among S. sisymbriifolium and other Solanum species (S. intergrifolium and S. toxicarium). Regardless of a breed, as the IOA concentration increases, the cell division tends to decrease. As the influence of the media on the colony formation, we could get 5 colonies from the fusion of S. sisymbriifolium and IOA-treated S. integrifolium protoplast, but none was observed in other fusions. As a result of analyzing their IDH isozyme, we found a somatic hybrid in 2 objects.

• Clinical and Experimental Reproductive Medicine
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• 제38권1호
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• pp.1-5
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• 2011

The maturation process of mammalian oocytes accompanies an extensive rearrangement of the cytoskeleton and associated proteins. As this process requires a delicate interplay between the cytoskeleton and its regulators, it is often targeted by various external and internal adversaries that affect the congression and/or segregation of chromosomes. Asymmetric cell division in oocytes also requires specific regulators of the cytoskeleton, including formin-2 and small GTPases. Recent literature providing clues regarding how actin filaments and microtubules interact during spindle migration in mouse oocytes are highlighted in this review.

• Journal of Microbiology and Biotechnology
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• 제18권1호
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• pp.55-58
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• 2008

Alanine racemase, a bacterial enzyme belonging to the fold-type III group of pyridoxal 5'-phosphate (PLP)-dependent enzymes, has been shown to catalyze the interconversion between L- and D-alanine. The alanine racemase from the pathogenic bacterium Enterococcus faecalis v583 has been overexpressed in E. coli and was shown to crystallize an enzyme at 295 K, using polyethylene glycol (PEG) 8000 as a precipitant. X-ray diffraction data to $2.5{\AA}$ has been collected using synchrotron radiation. The crystal is a member of the orthorhombic space group, $C222_1$ with unit cell parameter of a=94.634, b=156.516, $c=147.878{\AA},\;and\;{\alpha}={\beta}={\gamma}=90{\AA}$. Two or three monomers are likely to be present in the asymmetric unit, with a corresponding $V_m\; of\;3.38{\AA}^3\;Da^{-1}\;and\;2.26{\AA}^3\;Da^{-1}$ and a solvent content of 63.7% and 45.5%, respectively.

• Journal of Ginseng Research
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• 제48권3호
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• pp.266-275
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• 2024

Cancer stem cells (CSCs) are a rare subpopulation of cancer cells that exhibit stem cell-like characteristics, including self-renewal and differentiation in a multi-stage lineage state via symmetric or asymmetric division, causing tumor initiation, heterogeneity, progression, and recurrence and posing a major challenge to current anticancer therapy. Despite the importance of CSCs in carcinogenesis and cancer progression, currently available anticancer therapeutics have limitations for eradicating CSCs. Moreover, the efficacy and therapeutic windows of currently available anti-CSC agents are limited, suggesting the necessity to optimize and develop a novel anticancer agent targeting CSCs. Ginseng has been traditionally used for enhancing immunity and relieving fatigue. As ginseng's long history of use has demonstrated its safety, it has gained attention for its potential pharmacological properties, including anticancer effects. Several studies have identified the bioactive principles of ginseng, such as ginseng saponin (ginsenosides) and non-saponin compounds (e.g., polysaccharides, polyacetylenes, and phenolic compounds), and their pharmacological activities, including antioxidant, anticancer, antidiabetic, antifatigue, and neuroprotective effects. Notably, recent reports have shown the potential of ginseng-derived compounds as anti-CSC agents. This review investigates the biology of CSCs and efforts to utilize ginseng-derived components for cancer treatment targeting CSCs, highlighting their role in overcoming current therapeutic limitations.

• Biodesign
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• 제7권2호
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• pp.35-37
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• 2019

Xanthomonas oryzae pv. oryzae (Xoo) is a plant pathogen, which causes a bacterial blight of rice. The bacterial blight is one of the most devastating diseases of rice in most of the rice growing countries and there is no effective pesticide against bacterial blight. The β-ketoacyl-acyl carrier protein synthase III (FabH) plays a key role in fatty acid synthesis (FAS) and is a promising drug target for the development of antibacterial agents. Xoo0878 gene, a fabH gene, from Xoo was cloned and its gene product Xoo0878 was expressed, purified and crystallized. Xoo0878 crystal diffracted to 2.1Å resolution and belonged to the triclinic space group P1, with unit-cell parameters a = 57.3Å, b = 64.7Å, c = 104.2Å and α = 81.6°, β = 84.7°, γ = 74.4°. There are four monomers in the asymmetric unit, with a corresponding crystal volume per protein weight of 2.65 ų Da^-1 and a solvent content of 53.6%. Xoo0878 structure will be useful to develop new antibacterial agents against Xoo.