Antifungal effect of CopA3 monomer peptide via membrane-active mechanism and stability to proteolysis of enantiomeric d-CopA3

In our previous study, coprisin, a 43-mer defensin-like peptide, was derived from the dung beetle, Copris tripartitus, and a 9-mer CopA3 (monomer), truncated coprisin analog peptide, was designed. However, the antifungal effects of CopA3 are not known yet. In this study, the antifungal activity and mechanism of CopA3 were investigated and to develop a more effective antimicrobial peptide under physiological conditions, the enantiomeric d-CopA3 was designed. l- and d-CopA3 had a similar antifungal activity without chiral selectivity, and their activity was more potent than that of melittin used as a positive control. Furthermore, l- and d-CopA3 did not even show any hemolysis against human erythrocytes. Membrane studies using propidium iodide and bis-(1,3-dibutylbarbituric acid) trimethine oxonol [DiBAC₄(3)], suggested that the antifungal effect of l- and d-CopA3 was due to the membrane-active mechanism, by contrast with coprisin possessing apoptotic mechanism without membrane permeabilization. Finally, the proteolytic resistance and antifungal activity of l- and d-CopA3 against trypsin was analyzed by HPLC and colony count assay. The results showed that only d-CopA3 maintained a potent antifungal activity despite the proteolytic condition. Therefore, this study suggests that d-CopA3 has potential as a novel antimicrobial agent.     

Comparison of Fabrication Methods Based on Nanoimprinting Lithography for Plasmonic Color Filter Fabrication

The angle-variable tunable optical filter was strictly fabricated by two strategies of nanoimprint-coupled metal nanopatterning with improved cost-effectiveness and accessibility. The tunable optical properties and the performances of two strategies were experimentally examined and turned out to be well matched to numerical results. Tunable properties are obtained by three factors: size of fabricated Ag nanodisks, incident illumination angle, and fabrication strategies. The resonant extinction peak shifts were identified to show a large increase along with the increase in fabricated Ag disk size and increase in the incidence angle of illumination. When comparing a fabrication strategy, it was confirmed that the sample fabricated by the strip-off method has better stability on color changes with a consistent dependency on the incident angle. The presented strategies of fabrication are technically viable for obtaining well-defined plasmonic nanostructures so that it has the feasibility to apply for fascinating optical applications including display or tunable optical filters.

     

Ablation of Gadd45β ameliorates the inflammation and renal fibrosis caused by unilateral ureteral obstruction

The growth arrest and DNA damage‐inducible beta (Gadd45β) protein have been associated with various cellular functions, but its role in progressive renal disease is currently unknown. Here, we examined the effect of Gadd45β deletion on cell proliferation and apoptosis, inflammation, and renal fibrosis in an early chronic kidney disease (CKD) mouse model following unilateral ureteral obstruction (UUO). Wild‐type (WT) and Gadd45β‐knockout (KO) mice underwent either a sham operation or UUO and the kidneys were sampled eight days later. A histological assay revealed that ablation of Gadd45β ameliorated UUO‐induced renal injury. Cell proliferation was higher in Gadd45β KO mouse kidneys, but apoptosis was similar in both genotypes after UUO. Expression of pro‐inflammatory cytokines after UUO was down‐regulated in the kidneys from Gadd45β KO mice, whereas UUO‐mediated immune cell infiltration remained unchanged. The expression of pro‐inflammatory cytokines in response to LPS stimulation decreased in bone marrow‐derived macrophages from Gadd45β KO mice compared with that in WT mice. Importantly, UUO‐induced renal fibrosis was ameliorated in Gadd45β KO mice unlike in WT mice. Gadd45β was involved in TGF‐β signalling pathway regulation in kidney fibroblasts. Our findings demonstrate that Gadd45β plays a crucial role in renal injury and may be a therapeutic target for the treatment of CKD.     

Activation of Ni Particles into Single Ni–N Atoms for Efficient Electrochemical Reduction of CO2

Electrochemical reduction of carbon dioxide (CO₂) to fuels and value‐added industrial chemicals is a promising strategy for keeping a healthy balance between energy supply and net carbon emissions. Here, the facile transformation of residual Ni particle catalysts in carbon nanotubes into thermally stable single Ni atoms with a possible NiN₃ moiety is reported, surrounded with a porous N‐doped carbon sheath through a one‐step nanoconfined pyrolysis strategy. These structural changes are confirmed by X‐ray absorption fine structure analysis and density functional theory (DFT) calculations. The dispersed Ni single atoms facilitate highly efficient electrocatalytic CO₂ reduction at low overpotentials to yield CO, providing a CO faradaic efficiency exceeding 90%, turnover frequency approaching 12 000 h^?1, and metal mass activity reaching about 10 600 mA mg^?1, outperforming current state‐of‐the‐art single atom catalysts for CO₂ reduction to CO. DFT calculations suggest that the Ni@N₃ (pyrrolic) site favors *COOH formation with lower free energy than Ni@N₄, in addition to exothermic CO desorption, hence enhancing electrocatalytic CO₂ conversion. This finding provides a simple, scalable, and promising route for the preparation of low‐cost, abundant, and highly active single atom catalysts, benefiting future practical CO₂ electrolysis.     

The structure and antimicrobial potential of wasp and hornet (Vespidae) mastoparans: A review

Wasp venom is a complex mixture of biologically active components, including high molecular weight proteins, small peptides, bioactive amines, and amino acids. Peptides comprise up to 70% of dried venom. In social wasp venoms, three of the major peptide types are mastoparans, which cause mast cell degranulation, chemotactic peptides, which promote chemotaxis of polymorphonucleated leukocytes, and kinin‐related peptides, which are known to produce pain and increase vascular permeability. Among these, the bioactive tridecapeptide mastoparan is the most common and may even have antimicrobial activity. Herein we summarize the results of studies on vespid mastoparans, focusing on hornets (Vespa spp.) identified following a systematic literature search for mastoparans of hornets in the genus Vespa, the most active mastoparan research taxon. The common features of hornet mastoparans are C‐terminal amidation, amphipathic helical structure, and multiple functions such as mast cell degranulation and hemolysis, as well as membrane permeabilization. Most interestingly, all tested hornet mastoparans have strong antimicrobial activities, suggesting that they can provide useful insights into and opportunities for development of novel antibacterial peptides.     

Evolutionary processes of melanomas from giant congenital melanocytic nevi

Melanoma can develop in a congenital melanocytic nevus (CMN). In fact, a large CMN is associated with a high risk of developing melanoma. Although melanomas arising from CMNs are thought to have a pathogenesis distinct from conventional melanomas, no studies have been conducted on the evolution or tumor heterogeneity of CMN melanomas. We applied multi‐region whole‐exome sequencing to investigate the clonal nature of driver events and evolutionary processes in CMNs and melanomas arising from CMNs. In two patients, we observed an independent subclonal evolution in cancerized fields of CMNs and chromosome 8q amplification in both melanomas arising from CMNs. The amplification of MYC, located in chromosome 8q, was correlated with the percentage of tumor cells expressing high levels of MYC protein detected in melanoma cells by immunohistochemistry. Our analysis suggests that each CMN cell may evolve sporadically and that amplification of MYC might be a key event for melanoma development in CMNs.     

Nanobiohybrid Material‐Based Bioelectronic Devices

Biomolecules, especially proteins and nucleic acids, have been widely studied to develop biochips for various applications in scientific fields ranging from bioelectronics to stem cell research. However, restrictions exist due to the inherent characteristics of biomolecules, such as instability and the constraint of granting the functionality to the biochip. Introduction of functional nanomaterials, recently being researched and developed, to biomolecules have been widely researched to develop the nanobiohybrid materials because such materials have the potential to enhance and extend the function of biomolecules on a biochip. The potential for applying nanobiohybrid materials is especially high in the field of bioelectronics. Research in bioelectronics is aimed at realizing electronic functions using the inherent properties of biomolecules. To achieve this, various biomolecules possessing unique properties have been combined with novel nanomaterials to develop bioelectronic devices such as highly sensitive electrochemical‐based bioelectronic sensing platforms, logic gates, and biocomputing systems. In this review, recently reported bioelectronic devices based on nanobiohybrid materials are discussed. The authors believe that this review will suggest innovative and creative directions to develop the next generation of multifunctional bioelectronic devices.     

Insulin signaling pathway assessment by enhancing antioxidant activity due to morin using in vitro rat skeletal muscle L6 myotubes cells

Molecular Biology Reports - Plant-derived phytochemicals such as flavonoids have been explored to be powerful antioxidants that protect against oxidative stress-related diseases. In the present...     

Cathelicidin ΔPb-CATH4 derived from Python bivittatus accelerates the healing of Staphylococcus aureus-infected wounds in mice

The effects of ΔPb-CATH4, a cathelicidin derived from Python bivittatus, were evaluated against Staphylococcus aureus-infected wounds in mice. These effects were comparable to those of classical antibiotics. ΔPb-CATH4 was resistant to bacterial protease but not to porcine trypsin. A reduction in the level of inflammatory cytokines and an increase in the migration of immune cells was observed in vitro. Thus, ΔPb-CATH4 can promote wound healing by controlling infections including those caused by multidrug-resistant bacteria via its immunomodulatory effects.

     

Anaerocolumna sedimenticola sp. nov., isolated from fresh water sediment

Strain CBA3638^T was isolated from the Geum River sediment, Republic of Korea. The cells of strain CBA3638^T were Gram-stain-positive, strictly anaerobic, rod-shaped, and 0.5–1.0 μm wide, and 4.0–4.5 μm long. Optimal growth occurred at 37 °C, pH 7.0, and 1.0% (w/v) NaCl. Based on the 16S rRNA gene sequence, the phylogenetic analysis showed that strain CBA3638^T belongs to the genus Anaerocolumna in the family Lachnospiraceae, and is most closely related to Anaerocolumna cellulosilytica (94.6–95.0%). The DDH value with A. cellulosilytica SN021^T showed 15.0% relatedness. The genome of strain CBA3638^T consisted of one circular chromosome that is 5,500,435 bp long with a 36.7 mol% G?+?C content. The genome contained seven 16S-5S-23S rRNA operons and one antibiotic resistance-related transporter gene (mefA). Quinones were not detected. The predominant cellular fatty acids were C_16:0 and C_14:0 and the polar lipids were diphosphatidylglycerol, phosphatidylcholine, and uncharacterised polar lipids. Based on the polyphasic taxonomic analysis, we propose strain CBA3638^T as a novel species in the genus Anaerocolumna, with the name Anaerocolumna sedimenticola sp. nov. The type strain is CBA3638^T (=?KACC 21652^T?=?DSM 110663^T).