Publications by authors named "Ji Hui Seo"

Article Synopsis
  • Bacteria from the SAR202 clade, part of the Chloroflexota phylum, are found in oceans but couldn't be grown in labs until now.
  • Researchers successfully cultivated these slow-growing bacteria using a method called dilution-to-extinction, noting they are sensitive to light.
  • The bacteria have large genomes with numerous genes for enzymes, suggesting they can process a variety of organic compounds, including specific sugars and their derivatives, through multiple metabolic pathways.
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To boost the photoelectrochemical water oxidation performance of hematite photoanodes, high temperature annealing has been widely applied to enhance crystallinity, to improve the interface between the hematite-substrate interface, and to introduce tin-dopants from the substrate. However, when using additional dopants, the interaction between the unintentional tin and intentional dopant is poorly understood. Here, using germanium, we investigate how tin diffusion affects overall photoelectrochemical performance in germanium:tin co-doped systems.

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  • A fast-charging battery is crucial for electric vehicles, with high-capacity silicon anodes being a promising alternative to traditional carbon materials.
  • However, silicon anodes face challenges like fracturing during charging and slow ion transport, which limit their performance.
  • Researchers have discovered that doping silicon with small amounts of sulfur improves lithium ion conductivity and stability, leading to a silicon battery anode that outperforms current commercial options in fast charging and energy density.
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The actinobacterial acI lineage is among the most successful and ubiquitous freshwater bacterioplankton found on all continents, often representing more than half of all microbial cells in the lacustrine environment and constituting multiple ecotypes. However, stably growing pure cultures of the acI lineage have not been established despite various cultivation efforts based on ecological and genomic studies on the lineage, which is in contrast to the ocean from which abundant microorganisms such as Prochlorococcus, Pelagibacter, and Nitrosopumilus have been isolated. Here, we report the first two pure cultures of the acI lineage successfully maintained by supplementing the growth media with catalase.

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Glutathione (GSH)-deprived Dictyostelium discoideum accumulates methylglyoxal (MG) and reactive oxygen species (ROS) during vegetative growth. However, the reciprocal effects of the production and regulation of these metabolites on differentiation and cell motility are unclear. Based on the inhibitory effects of γ-glutamylcysteine synthetase (gcsA) disruption and GSH reductase (gsr) overexpression on aggregation and culmination, respectively, we overexpressed GSH-related genes encoding superoxide dismutase (Sod2), catalase (CatA), and Gcs, in D.

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  • A study was conducted to understand how spatial and environmental factors affect bacterial communities in the littoral sea of the South Sea of Korea, utilizing advanced 16S rRNA gene sequencing techniques.
  • The analysis revealed a high diversity of bacterial sequences, predominantly belonging to Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes, with notable differences in community structure based on proximity to the coastline.
  • Significant findings included the prevalence of SAR11 clade in coastal areas and Roseobacter in offshore areas, along with unique spatial patterns for other groups like Actinobacteria and Cyanobacteria, highlighting the influence of environmental factors like phosphate levels on community composition.
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Reduced glutathione (GSH) is an essential metabolite that performs multiple indispensable roles during the development of Dictyostelium. We show here that disruption of the gene (gcsA-) encoding y-glutamylcysteine synthetase, an essential enzyme in GSH biosynthesis, inhibited aggregation, and that this developmental defect was rescued by exogenous GSH, but not by other thiols or antioxidants. In GSH-depleted gcsA- cells, the expression ofa growth-stage-specific gene (cprD) was not inhibited, and we did not detect the expression of genes that encode proteins required for early development (cAMP receptor, carA/cAR1; adenylyl cyclase, acaA/ACA; and the catalytic subunit of protein kinase A, pkaC/PKA-C).

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We investigated the function of homeodomain-containing protein Hbx4 in Dictyostelium discoideum. Hbx4-overexpressing cells (Hbx4(OE)) displayed defects in growth rate and cytokinesis and showed differences in slug motility and cell-type proportioning from KAx3. Furthermore, the overexpression of Hbx4 inhibited the induction of cadA, which encoded the Ca(2+)-dependent cell adhesion molecule DdCAD-1, despite expression of csaA and gpaB.

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6-(Substituted-phenyl)amino-5,8-quinazolinediones (3) were synthesised by regioselective substitution of 5,8-quinazolinedione (5) with appropriate arylamines in the presence of Ce(III) ions. All synthesised 5,8-quinazolinediones 3 showed a potent and efficacious inhibitory effect on the acetylcholine (ACh)-induced vasorelaxation of rat aorta with the endothelium. The quinones 3, at a low concentration of 0.

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