A novel Golgi mannosidase inhibitor: Molecular design,synthesis, enzyme inhibition,and inhibition of spheroid formation

Effective chemotherapy for solid cancers is challenging due to a limitation in permeation that prevents anticancer drugs from reaching the center of the tumor, therefore unable to limit cancer cell growth. To circumvent this issue, we planned to apply the drugs directly at the center by first collapsing the outer structure. For this, we focused on cell–cell communication (CCC) between N-glycans and proteins at the tumor cell surface. Mature N-glycans establish CCC; however, CCC is hindered when numerous immature N-glycans are present at the cell surface. Inhibition of Golgi mannosidases (GMs) results in the transport of immature N-glycans to the cell surface. This can be employed to disrupt CCC. Here, we describe the molecular design and synthesis of an improved GM inhibitor with a non-sugar mimic scaffold that was screened from a compound library. The synthesized compounds were tested for enzyme inhibition ability and inhibition of spheroid formation using cell-based methods. Most of the compounds designed and synthesized exhibited GM inhibition at the cellular level. Of those, AR524 had higher inhibitory activity than a known GM inhibitor, kifunensine. Moreover, AR524 inhibited spheroid formation of human malignant cells at low concentration (10 µM), based on the disruption of CCC by GM inhibition.     

DNA Methylation and Histone H1 Jointly Repress Transposable Elements and Aberrant Intragenic Transcripts

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Candidate Cancer Driver Mutations in Distal Regulatory Elements and Long-Range Chromatin Interaction Networks

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Core Components of the Nuclear Pore Bind Distinct States of Chromatin and Contribute to Polycomb Repression

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Biodegradation of organophosphorus insecticides by two organophosphorus hydrolase genes (opdA and opdE) from isolated Leuconostoc mesenteroides WCP307 of kimchi origin

This study is aimed to reveal the molecular incidence of organophosphorus insecticides degradation during the fermentation of Korean food yeulmu-mulkimchi. To this end, two opdA and opdE which consist of 930 and 894 bp that encode 309 and 297 amino acids, respectively, were cloned from the Leuconostoc mesenteroides WCP307 strain that was isolated from chlorpyrifos (CP) impregnated kimchi. The Escherichia coli that harbored the opdA and opdE genes depleted a CP concentration of 72% and 83%, respectively, in an M9 medium after 6 days. The OpdA and OpdE enzymes molecular weights were estimated to be approximately 35 and 33 kDa and showed optimal activities at 30 °C with a pH of 7.0 and 6.0, respectively. However, the mutated OpdA (Ser128 → Ala128) and OpdE (Ser129 → Ala129) enzymes had no activities on OP insecticides and ρ-nitrophenyl butyrate substrates. In addition, the OpdA and OpdE enzymes showed profound catalytic activities against cadusafos, comnaphos, diazinon, dyfonate, ethoprophos, fenamiphos, methylparathion, and parathion insecticides. Therefore, it is assumed that OpdA and OpdE enzymes detoxified the pesticides contaminated kimchi composition like Chinese cabbages during fermentation. Furthermore, the OpdA and OpdE enzymes augmented the diversity of new LAB-opd enzymes group in nature.     

An Oscillating MinD Protein Determines the Cellular Positioning of the Motility Machinery in Archaea

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Domestication of the Emblematic White Cheese-Making Fungus Penicillium camemberti and Its Diversification into Two Varieties

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The AtXTH28 Gene, a Xyloglucan Endotransglucosylase/Hydrolase, is Involved in Automatic Self-Pollination in Arabidopsis thaliana

Successful automatic self-pollination in flowering plants isdependent on the correct development of reproductive organs.In the stamen, the appropriate growth of the filament, whichlargely depends on the mechanical properties of the cell wall,is required to position the anther correctly close to the stigmaat the pollination stage. Xyloglucan endotransglucosylase/hydrolases(XTHs) are a family of enzymes that mediate the constructionand restructuring of xyloglucan cross-links, thereby controllingthe extensibility or mechanical properties of the cell wallin a wide variety of plant tissues. Our reverse genetic analysishas revealed that a loss-of-function mutation of an ArabidopsisXTH family gene, AtXTH28, led to a decrease in capability forself-pollination, probably due to inhibition of stamen filamentgrowth. Our results also suggest that the role of AtXTH28 inthe development of the stamen is not functionally redundantwith its closest paralog, AtXTH27. Thus, our finding indicatesthat AtXTH28 is specifically involved in the growth of stamenfilaments, and is required for successful automatic self-pollinationin certain flowers in Arabidopsis thaliana.