We isolated 23 soil bacterial strains tolerating methaneseleninic acid (MSeA), an oxidized organoselenium metabolite. Among them, Pseudomonas sp. M10 exhibited the highest MSeA tolerance and converted MSeA into volatile...We isolated 23 soil bacterial strains tolerating methaneseleninic acid (MSeA), an oxidized organoselenium metabolite. Among them, Pseudomonas sp. M10 exhibited the highest MSeA tolerance and converted MSeA into volatile dimethyldiselenide, consistent with a redox-driven, nonenzymatic process. This is the first report of bacterially mediated MSeA volatilization, revealing a previously unrecognized microbial contribution to selenium flux between terrestrial and atmospheric compartments.
Carbonic anhydrase accelerates the hydration of carbon dioxide (CO₂) and is an attractive biocatalyst for carbon capture and utilization. Acinetobacter sp. Tol 5 shows high adhesiveness via its cell-surface protein AtaA....Carbonic anhydrase accelerates the hydration of carbon dioxide (CO₂) and is an attractive biocatalyst for carbon capture and utilization. Acinetobacter sp. Tol 5 shows high adhesiveness via its cell-surface protein AtaA. We previously demonstrated its application to bacterial immobilization and gas-phase bioproduction. Here, we developed Tol 5 cells expressing carbonic anhydrase and evaluated CO₂ conversion ability as whole-cell biocatalysts. A codon-optimized carbonic anhydrase from Sulfurihydrogenibium yellowstonense (SyCA) was produced in the cytoplasm, but the cells showed little activity as a whole-cell biocatalyst. To enhance activity, we fused six signal peptides (SPs) to SyCA for periplasmic expression. The Omp38-SP fusion of SyCA was properly processed to the mature size, yielding higher whole-cell activity. By contrast, the other constructs were either undetectable or remained unprocessed, resulting in lower activities. These results show that periplasmic expression of SyCA is important for efficient CO₂ hydration in Tol 5 cells as whole-cell biocatalysts.
Selaginellin A (Sela A), a derivative from Selaginella tamariscina, exerts antitriple-negative breast cancer effects in MDA-MB-231 cells. Proteomic profiling identified 1136 differentially expressed proteins after Sela A...Selaginellin A (Sela A), a derivative from Selaginella tamariscina, exerts antitriple-negative breast cancer effects in MDA-MB-231 cells. Proteomic profiling identified 1136 differentially expressed proteins after Sela A treatment, predominantly downregulated (n = 889). Enrichment analyses revealed that Sela A significantly downregulated pathways critical for DNA repair, replication, and cell cycle progression, while upregulating ribosomal biogenesis and protein processing. Mechanistically, Sela A acts as a PTP1B inhibitor (IC50 = 7.4 μm), binding key residues (PHE-182, GLU-186). This inhibition activates the mechanistic target of rapamycin complex 1 (mTOR). Consequently, mTOR activation stimulates ribosomal synthesis but concurrently triggers a p70S6K-mediated negative feedback loop, degrading IRS1. IRS1 loss suppresses Akt signaling, reducing expression of cell cycle proteins and inducing G1-phase arrest. Thus, Sela A may block MDA-MB-231 cell proliferation via PTP1B inhibition driving mTOR/IRS1/Akt dysregulation.
Amniotic fluid (AF) constitutes a dynamic environment containing diverse bioactive molecules derived from both maternal and fetal sources that support fetal development. As the fetus develops in continuous contact with A...Amniotic fluid (AF) constitutes a dynamic environment containing diverse bioactive molecules derived from both maternal and fetal sources that support fetal development. As the fetus develops in continuous contact with AF, it is plausible that AF influences the formation of the skin epidermis. However, the mechanisms through which AF promotes keratinocyte differentiation remain largely unclear. Here, we showed that goat AF enhanced the expression of key functional proteins involved in epidermal barrier formation, including small proline-rich proteins, loricrin, and transglutaminase. We further obtained the bioactive fractions that promote the expression of these differentiation-related proteins through multistep protein fractionation via column chromatography. Proteomic analysis subsequently revealed 291 candidate proteins, including 85 distinct extracellular proteins, primarily grouped into calcium-binding proteins, proteases and their regulators, extracellular matrix components, and signaling molecules. Collectively, these results suggest that proteins secreted or released into AF contribute to establishing a microenvironment conducive to epidermal differentiation.
The taste of agricultural products and foods is an important factor in quality evaluation; thus, comparable taste data are useful for their production, marketing, branding, and distribution regardless of when or where th...The taste of agricultural products and foods is an important factor in quality evaluation; thus, comparable taste data are useful for their production, marketing, branding, and distribution regardless of when or where the data were obtained. To realize this concept, taste data need to be standardized. In this study, a method for standardizing the sourness and sweetness intensities of apple was established using a taste sensor system and a standard solution prepared from citric acid and sucrose. These taste substances are commonly used for standard solutions of other foods. Polyphenolic compounds that interfere with the sweetness sensor probe were removed from sample solutions using polyvinylpolypyrrolidone. The taste intensities estimated using this method showed good agreement with chemical analysis values highly correlated with human sensory evaluation data.
Kimoto seed mash is a traditional fermentation starter used in sake brewing that contains sufficient lactic acid produced by various lactic acid bacteria (LAB). To determine the factors influencing their community, we in...Kimoto seed mash is a traditional fermentation starter used in sake brewing that contains sufficient lactic acid produced by various lactic acid bacteria (LAB). To determine the factors influencing their community, we investigated the actively operating LAB species in addition to brewing and chemical components in the early and middle periods over different brewing years in the same sake brewery. The results showed that the composition and changes in the LAB species and amino acid profiles varied annually. Furthermore, reproduction of changes in the LAB community using a modified synthetic medium demonstrated the dependency of certain LAB strains on specific amino acids. Notably, we found that the behaviors of cocci such as Leuconostoc citreum, Lactococcus raffinolactis, Leuconostoc suionicum, and Pediococcus pentosaceus were affected by tryptophan or tyrosine requirements for each species. The metabolic activities of some LAB species were also reflected in the organic acid profile of kimoto seed mash.
Co-administration of histidine and soy isoflavones induced beige adipogenesis in male rats, as demonstrated by the formation of multilocular lipid droplets and increased uncoupling protein 1 gene expression in white adip...Co-administration of histidine and soy isoflavones induced beige adipogenesis in male rats, as demonstrated by the formation of multilocular lipid droplets and increased uncoupling protein 1 gene expression in white adipose tissue. This response was accompanied by fat depot-specific enhancement of mitochondrial activity and suppression of lipogenesis, suggesting the potential for dietary strategies to combat obesity via beige adipocytes activation.
Glucagon dysregulation is a hallmark of type 2 diabetes mellitus (T2DM), yet its early hepatic effects remain unclear. Here, we demonstrate that glucagon-induced gluconeogenesis is markedly enhanced in primary hepatocyte...Glucagon dysregulation is a hallmark of type 2 diabetes mellitus (T2DM), yet its early hepatic effects remain unclear. Here, we demonstrate that glucagon-induced gluconeogenesis is markedly enhanced in primary hepatocytes from prediabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a well-established model of human T2DM. Compared to control LETO rats, OLETF hepatocytes showed significantly higher glucagon-stimulated expression of gluconeogenic genes (Pepck, G6pase, and Fbp1) at both mRNA and protein levels, along with elevated glucose production. Notably, mRNA decay analysis revealed prolonged half-lives of gluconeogenic transcripts in OLETF hepatocytes, indicating enhanced mRNA stability as a novel mechanism contributing to increased hepatic glucose output. These findings highlight aberrant glucagon responsiveness and posttranscriptional regulation as potential predisposing factors in genetically susceptible models prior to the onset of overt metabolic abnormality, which may be of interest for preventive or therapeutic strategies for controlling fasting hyperglycemia.
Lignocellulosic biomass is a carbon-neutral resource crucial to advancing a bio-based economy. The filamentous fungus Talaromyces cellulolyticus demonstrates superior biomass saccharification efficiency compared to conve...Lignocellulosic biomass is a carbon-neutral resource crucial to advancing a bio-based economy. The filamentous fungus Talaromyces cellulolyticus demonstrates superior biomass saccharification efficiency compared to conventional enzyme-producing fungi, making it a promising host for enzymatic biomass conversion. To enable molecular studies, we developed a robust genetic transformation system for T. cellulolyticus and identified key transcription factors regulating saccharifying enzyme genes, classified into 3 functional groups. Manipulation of these regulators significantly enhanced enzyme production. Additionally, we purified individual enzymes and conducted biochemical and structural analyses, leading to the discovery of a novel xylanase with unique side-chain recognition. The integration of genetic and enzymatic insights advances both our understanding of fungal saccharification systems and the development of more efficient biomass-to-sugar conversion strategies for sustainable biotechnological applications.
Interleukin-1β (IL-1β) is a central proinflammatory cytokine implicated in osteoarthritis (OA), but its precise role in chondrocyte apoptosis remains to be fully elucidated. In this study, we demonstrate that IL-1β trigg...Interleukin-1β (IL-1β) is a central proinflammatory cytokine implicated in osteoarthritis (OA), but its precise role in chondrocyte apoptosis remains to be fully elucidated. In this study, we demonstrate that IL-1β triggers mitophagy in chondrocytes by promoting Parkin translocation and p62 recruitment to damaged mitochondria, thereby reducing mitochondrial dysfunction and apoptosis. Loss of p62 resulted in impaired mitophagy, excessive mitochondrial superoxide accumulation, and increased cell death. Mechanistically, IL-1β enhanced NF-κB (RelA) phosphorylation at Ser276 and Ser536, accompanied by elevated Mitogen and stress-activated kinase-1 (MSK1) expression. Inhibition of MSK1 selectively suppressed Ser276 phosphorylation without affecting Ser536, leading to reduced p62 expression and disrupted mitophagy. These findings reveal a previously unrecognized intrinsic regulatory mechanism by which IL-1β limits its own apoptosis-promoting effect through activation of the NF-κB (RelA) Ser276-p62-mitophagy axis. This pathway facilitates the clearance of damaged mitochondria and preserves chondrocyte viability, offering potential therapeutic insight into inflammation-associated cartilage degeneration in OA.
Selenium is an essential trace element in many organisms but becomes toxic at elevated concentrations. At moderately increased, non-lethal levels, selenite triggers both selenium utilization and stress responses in micro...Selenium is an essential trace element in many organisms but becomes toxic at elevated concentrations. At moderately increased, non-lethal levels, selenite triggers both selenium utilization and stress responses in microorganisms. However, the thresholds of such responses in archaea remain poorly understood. Here, we investigated the effects of elevated yet non-inhibitory concentrations of selenite on growth and gene expression in the methanogenic archaeon Methanococcus maripaludis JJ. We observed no significant impact on growth rate or cell yield, even at 100 µm selenite. RNA sequencing and reverse transcription-quantitative polymerase chain reaction analyses revealed differential expression of genes involved in methanogenesis and transport systems, which may contribute to maintaining growth under elevated selenite. Our findings suggest that the transcriptional response to selenite in M. maripaludis is initiated at low concentrations (eg <1 µm) and remains saturated across a hundredfold range (up to 100 µm), without inducing stress responses or impairing growth.
Royal jelly (RJ), secreted by honeybees, contains major fatty acids such as 10-hydroxy-2-decenoic acid and 10-hydroxydecanoic acid, which are considered to contribute to bone metabolism. However, these fatty acids are ra...Royal jelly (RJ), secreted by honeybees, contains major fatty acids such as 10-hydroxy-2-decenoic acid and 10-hydroxydecanoic acid, which are considered to contribute to bone metabolism. However, these fatty acids are rapidly metabolized in the liver following ingestion, resulting in 2-decenoic acid (2DA) and sebacic acid (SA), respectively. Therefore, elucidating the roles of these metabolites in bone metabolism is of considerable importance. In this study, we focused and investigated the effects of 2DA and SA on osteoblast differentiation using osteoblast-lineage cells. SA treatment significantly upregulated the expression of osteoblast marker genes whereas 2DA had no apparent effect. In addition, SA enhanced alkaline phosphatase activity, a typical marker of osteoblast differentiation and mineralization.
Inulin, a soluble dietary fiber, is widely recognized for its gut health benefits; however, its role in the progression of ulcerative colitis remains unclear. In this study, we investigated the effects of inulin suppleme...Inulin, a soluble dietary fiber, is widely recognized for its gut health benefits; however, its role in the progression of ulcerative colitis remains unclear. In this study, we investigated the effects of inulin supplementation on colitis induced by administering dextran sodium sulfate (DSS) to BALB/c mice. Mice were fed diets containing 10% inulin or cellulose, followed by administration of 2% DSS in drinking water. Inulin-supplemented mice exhibited a higher disease activity index and more severe epithelial damage compared to cellulose-fed controls. Similar pathological features were observed in mice administered polyethylene glycol to induce osmotic diarrhea, suggesting that increased luminal osmotic pressure may exacerbate colitis. Notably, co-administration of polycarbophil calcium with inulin ameliorated clinical symptoms and attenuated tissue damage. These findings suggest that inulin may aggravate colitis, potentially through increased luminal osmotic pressure. Therefore, managing osmotic diarrhea may represent a therapeutic strategy to mitigate colitis symptoms associated with certain dietary fibers.
Glycoside hydrolase family 27 (GH27) consists primarily of exo-acting enzymes, including α-galactosidase, α-N-acetylgalactosaminidase, β-l-arabinopyranosidase, and isomalto-dextranase. Here, we examined the gene expressi...Glycoside hydrolase family 27 (GH27) consists primarily of exo-acting enzymes, including α-galactosidase, α-N-acetylgalactosaminidase, β-l-arabinopyranosidase, and isomalto-dextranase. Here, we examined the gene expression profiles and biochemical characteristics of a multi-domain protein, Fjoh_4436 (named FjGH27A), which contains a GH27 catalytic domain and is encoded upstream of the previously described branched dextran utilization locus in Flavobacterium johnsoniae. Expression of this gene increased 7.7-fold when cultured with α-(1→2)- and α-(1→3)-branched dextran, produced by Leuconostoc citreum S-32, as the carbon source, compared with cultures using glucose or linear dextran. The catalytic domain of FjGH27A exhibited hydrolytic activity against linear dextran and produced isomaltooligosaccharides of various sizes in an endo-acting manner. The enzyme showed the highest activity toward linear dextran at pH 5.5-6.0 and 25 °C-30 °C. This represents the first identification of an endo-acting enzyme in the GH27 family, offering new insights into the mechanism of branched dextran degradation mediated by FjGH27A.
Glucagon-like peptide-1 (GLP-1) is a gastrointestinal hormone that suppresses postprandial glycemia and appetite. Glucagon-like peptide-1 secretion is promoted by various nutrients; however, studies on the effects of ora...Glucagon-like peptide-1 (GLP-1) is a gastrointestinal hormone that suppresses postprandial glycemia and appetite. Glucagon-like peptide-1 secretion is promoted by various nutrients; however, studies on the effects of orally administered amino acids on GLP-1 secretion are limited. This study investigated the acute effects of l-lysine (Lys) on GLP-1 secretion in vivo and explored the underlying mechanisms. In male Sprague-Dawley rats, oral administration of Lys, but not l-Alanine (Ala), elevated plasma GLP-1 concentrations, with comparable to or higher potency compared to other amino acids known to stimulate GLP-1 secretion. Duodenal administration of CaSR antagonist attenuated Lys-induced GLP-1 secretion. Oral co-administration of Lys and calcium potently promoted GLP-1 secretion and lowered glycemia under an oral glucose tolerance test. These findings demonstrate that Lys potently induces GLP-1 secretion in vivo, and the combination of Lys and calcium has translational potential as a potent GLP-1 releasing strategy for the management of blood glucose levels.
Jasmonates, including (+)-7-iso-jasmonic acid and related compounds, are plant hormones that regulate both developmental and defense responses. Among jasmonates, 12-hydroxyjasmonates, such as 12-hydroxyjasmonic acid (12-...Jasmonates, including (+)-7-iso-jasmonic acid and related compounds, are plant hormones that regulate both developmental and defense responses. Among jasmonates, 12-hydroxyjasmonates, such as 12-hydroxyjasmonic acid (12-OH-JA) and 12-hydroxyjasmonoyl-l-isoleucine (12-OH-JA-Ile), are commonly observed in various plant species. 12-Hydroxyjasmonates regulate jasmonate responses, both dependent and independent of CORONATINE-INSENSIVE 1 and JASMONATE ZIM-DOMAIN proteins, which are the most studied jasmonate co-receptors. This review summarizes the existence, biosynthesis, metabolism, bioactivities, and biological functions of 12-hydroxyjasmonates.
Cytochrome P450s (CYPs) and their associated reductases (CPRs) play a central role in plant secondary metabolism. These enzymes operate on lipid bilayers and require cofactors such as heme, FAD, and FMN. In this study, w...Cytochrome P450s (CYPs) and their associated reductases (CPRs) play a central role in plant secondary metabolism. These enzymes operate on lipid bilayers and require cofactors such as heme, FAD, and FMN. In this study, we developed an in vitro system to reconstitute CYPs and CPRs as functional enzymes on liposomes. As model proteins, we selected cinnamate 4-hydroxylase (C4H) from Arabidopsis thaliana and its redox partner ATR1. We investigated optimal conditions for incorporating cofactors into C4H and ATR1 and successfully reconstituted their catalytic activity. Hematin was found to be more effective than hemin as a heme source for C4H activation. Both C4H and ATR1 were embedded in liposomes, and the catalytic activity of C4H was significantly enhanced when both proteins were co-synthesized. These results highlight the importance of functional protein-protein interaction between C4H and ATR1 in achieving efficient electron transfer and catalytic function in vitro.
A single-step synthesis of farinomalein A, a naturally occurring maleimide, by the radical-mediated introduction of an isopropyl group to bromomaleic anhydride and one-pot maleimide formation with β-alanine is reported....A single-step synthesis of farinomalein A, a naturally occurring maleimide, by the radical-mediated introduction of an isopropyl group to bromomaleic anhydride and one-pot maleimide formation with β-alanine is reported. Antimicrobial testing of natural and unnatural farinomaleins synthesized using this protocol demonstrates that farinomalein A and some unnatural analogs are active against Bacillus subtilis, and one unnatural analog is active against Escherichia coli. The possible inhibitory activity of bacterial membrane and/or cell wall functions of farinomalein A was indicated by cell morphological studies.
This study investigated the saponin fraction (SF) from Panax japonicus aerial parts against NAFL. The SF was isolated from P. japonicus aerial parts using D-101 macroporous resin, containing 6 identified ginsenosides. Th...This study investigated the saponin fraction (SF) from Panax japonicus aerial parts against NAFL. The SF was isolated from P. japonicus aerial parts using D-101 macroporous resin, containing 6 identified ginsenosides. The SF could reduce the accumulation of lipids in liver and the hepatic index, decrease the levels of TC and triglyceride in serum and in liver, and decrease the levels of Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT) in serum. Additionally, the SF could increase the SOD and GSH-Px levels while reducing the levels of Malondialdehyde (MDA), Tumor Necrosis Factor (TNF-α), Interleukin (IL-1β), and Free Fatty Acids (FFA) in the liver. After treatment with SF, the AMP-activated protein kinase (AMPK)/ACC signaling pathway was activated through phosphorylation of AMPK and ACC, and the expression of HMG-CoA reductase (HMGCR) was inhibited, thereby reducing lipids synthesis. The results indicated that SF could treat NAFL by up-regulating the AMPK/ACC signaling pathway while inhibiting the expression of HMGCR.
To enhance the transformation efficiency of Bacillus subtilis Marburg 168 using PCR DNA fragments, we optimized the competent cell preparation by adding Mn2+ to the competence medium. This Mn2+ addition promoted both cel...To enhance the transformation efficiency of Bacillus subtilis Marburg 168 using PCR DNA fragments, we optimized the competent cell preparation by adding Mn2+ to the competence medium. This Mn2+ addition promoted both cell growth and increased transformation frequency. Moreover, we determined the necessary length of the homologous sequence on each end to achieve practically sufficient transformation through double crossover recombination.