Bemisia tabaci is a major global pest causing severe crop losses through phloem feeding and virus transmission, with heavy insecticide use driving resistance. Pepper (C. annuum) is naturally resistant to the MEAM1 whitefly, offering a model for studying inducible plant defenses. Metabolomic analysis revealed that psoralen accumulates in pepper leaves after whitefly feeding, a secondary metabolite known for insecticidal properties. Bioassays showed that psoralen significantly reduces adult survival and oviposition. Biochemical assays further indicated that psoralen inhibits key whitefly detoxification enzymes (GSTs, CarEs) and digestive enzymes (cellulase, α-amylase). These findings identify psoralen as an inducible defense metabolite contributing to pepper resistance against B. tabaci and highlight its potential for sustainable whitefly control through crop improvement or botanical insecticide development.

Despite their apparent relevance to Riesling wine aroma, volatile polyfunctional thiols remain understudied. This work profiles thiols in a collection of Riesling wines through analytical and sensory approaches. Heart-cutting multidimensional gas chromatography mass spectrometry/olfactometry screening revealed 13 odorous zones of high sensorial relevance, with four thiols unequivocally identified as 3-sulfanylhexan-1-ol, ethyl 3-sulfanylpropionate, ethyl 2-sulfanylpropionate, and trans-2-methyl-3-tetrahydrofuranthiol. Five additional candidate thiols with corresponding odorous zones were confirmed by ultrahigh-performance liquid chromatography quadrupole Orbitrap high-resolution mass spectrometry (UHPLC Orbitrap HRMS). UHPLC Orbitrap HRMS also allowed the quantitation of 12 thiols, as well as the detection of two new monoterpenoid thiols, 1-p-menthene-8-thiol and trans-p-menthane-3-one-8-thiol, in Vitis vinifera wine for the first time. Their odor detection thresholds in model wine were determined as 0.076 and 22.9 ng/L, respectively. Further sensory evaluations demonstrated the contributions to "peachy" and "tropical" notes in Riesling wine through a combination of 3-sulfanylhexan-1-ol and 3-sulfanylheptan-1-ol.

Fungi contain the most complex chitin synthase family, which contributes to chitin biosynthesis and cell wall rigidity. In the past decades, their functions involved in morphological diversity, viability, and virulence of fungi have been well investigated using typical molecular methods such as gene knockout or gene silence, which seems to give a simple aspect of their comprehensive roles. The present review summarized the comprehensive advances of chitin synthases including their classification, their precise structures including catalytic and noncatalytic protein domains, the catalytic mechanisms of chitin biosynthesis and translocation, and roles in cell wall formation, cell separation, and cell viability to provide the references for understanding and guiding the discovery of the novel antifungal drugs targeting the chitin synthases according to their structural basis to offer significant effects and lower resistance development.

This study obtained a novel chitinase gene (MlChi54) from Myxococcus landrumensis. MlChi54 has been successfully expressed, and the enzyme exhibited a chitinase activity of 10 U mg-1. Furthermore, MlChi54 demonstrated hydrolytic activity toward chitosan (2.6 U mg-1), exhibiting substrate promiscuity. Various aminooligosaccharides were produced by MlChi54 hydrolysis of chitosan (75% deacetylation). High-performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS) analyses were used to demonstrate that GlcNAc, (GlcNAc)2, and GlcNAc-β-1,4-GlcN-β-1,4-GlcNAc were the predominant components. A comparative structural analysis of three chitinases revealed that the catalytic groove of MlChi54 exhibited a negative electrostatic potential, while the distinctive groove architecture promoted enzymatic activity against chitosan. Furthermore, molecular dynamics (MD) simulations indicated that MlChi54 exhibited relatively stable conformations with three distinct deacetylated chitosan complexes. These unique enzymatic properties and structural characteristics may make MlChi54 a good candidate for the production of various aminooligosaccharides in the food, pharmaceutical, and agricultural industries.

Trichomes are key physical and chemical barriers in plants against herbivorous insects, but their development and role in strawberry insect resistance remain unclear. This study found that overexpressing FaGAPC2, a glycolytic gene, increased glandular trichome density and nonglandular trichome density while raising lignin content by 26.8%. Multiomics analysis revealed that FaGAPC2 activates phenylpropanoid biosynthesis, boosting levels of hydroferulic acid, kaempferol, and tetrandrine, reducing Tetranychus urticae damage by 61.5-82.8%. Y1H, LUC, and EMSA assays confirmed that bZIP transcription factor FaTRAB1 directly activates FaGAPC2. FaTRAB1 overexpression enhanced trichome density, pectin/cellulose content, and lignin accumulation by upregulating FaCSE and FaHCT while increasing the leaf thickness, forming a robust mechanical barrier. These findings demonstrate how the FaTRAB1-FaGAPC2 module enhances mite resistance via trichome development, lignin deposition, and insecticidal metabolite synthesis, offering new strategies for breeding pest-resistant strawberries and developing plant-based acaricides.

To explore transglycosidase application potential in starch processing and baking, a Bacillus inaquosorum strain with high amylopectin debranching activity was isolated and identified from the soil. Its neopullulanase gene (Binp) was cloned and heterologously expressed in Escherichia coli BL21. The recombinant enzyme reBinp, which requires a metal ion, had optimal catalytic activity at 35 °C and pH 7.0, efficiently hydrolyzed α-(1,6)-glycosidic bonds. Synergistic hydrolysis and transglycosylation effects were displayed when reBinp acted with Aspergillus niger α-transglucosidase (Antg). Adding reBinp and Antg (each of 1000 U/kg wheat flour) significantly improved bread quality and increased specific volume, hardness, gumminess, chewiness, cohesiveness, and storage stability. Mechanistically, the mixed enzymes decreased the relative crystallinity and gelatinization enthalpy of dough to 14.5% and 3.95 mJ/mg, respectively, while increasing the FTIR R1047/1022 ratio to 1.70. This study provides a solid basis for the synergistic application of neopullulanase and α-transglucosidase in starch biotransformation and the baking industry.

Cellulose depolymerization into glucose requires the synergistic action of endoglucanase, exoglucanase, and β-glucosidase. In this study, Bacillus subtilis DLG endoglucanase (BsEGL) and its family 3 carbohydrate-binding module (CBM3)-truncated mutant (BsEGLCD) were heterologously expressed in Escherichia coli BL21(DE3) and characterized. Both enzymes displayed optimal activity at 50 °C and pH 4.5, with BsEGLCD exhibiting superior thermal stability and broader pH stability. Both enzymes maintained over 90% relative activity within 0.5-4.5 M NaCl. Notably, BsEGLCD exhibited superior ethanol tolerance compared to BsEGL. Kinetic analysis revealed that, compared to BsEGL, BsEGLCD exhibited a lower substrate affinity but a higher catalytic rate, while BsEGL showed a slightly higher catalytic efficiency. Molecular dynamics simulations revealed that the CBM3 module removal enhanced structural rigidity and reduced salt sensitivity, as evidenced by lower RMSF fluctuations and stable Rg under high ionic strength. Our findings highlighted the trade-off between substrate affinity and stability imparted by the CBM3 module.

Goat milk is highly nutritious and represents an ideal alternative for individuals allergic to cow's milk proteins. This study investigated changes in milk composition and metabolic profiles of Xinong Saanen dairy goats across four lactation stages: colostrum, early, peak, and midlactation. Conventional milk composition analysis combined with widely targeted metabolomics was applied to characterize stage-dependent metabolic variation. Milk fat, protein, lactose, solids-not-fat, and inorganic salt contents declined progressively with lactation, with significantly higher levels observed during the colostrum stage (P < 0.05). Metabolomic analysis identified 738 metabolites exhibiting distinct stage-specific patterns, among which d-glucose-1,6-bisphosphate, N1-acetylspermine, and Ser-Ile were consistently differentiated across lactation stages. Correlation analysis further revealed several metabolites significantly associated with milk composition traits. These findings provide insights into metabolic regulation underlying dynamic changes in goat milk composition during lactation and offer a basis for quality evaluation and stage-specific nutritional management.

Dendrobium officinale Kimura et Migo, a valuable medicinal orchid, thrives in mountainous environments, the specific habitat factors promoting polysaccharide accumulation in wild plants. This study explored how light regulates phosphorus uptake in D. officinale and how light and phosphorus interact to influence polysaccharide synthesis. We found that red light promoted phosphorus absorption and induced polysaccharide accumulation under low phosphorus. Transcriptomic analysis revealed the upregulated expression of phosphate transporters DoPHT1;2 and DoPHT1;6 under red light. Transcription factors DoHY5 and DoPIF5 directly bound to the promoters of DoPHT1 genes and regulated the transporter expression. Additionally, DoPHT1;2 and DoPHT1;6 localized to the cell membrane and functioned as high-affinity phosphate transporters. Overexpression of DoHY5 enhanced phosphorus uptake and DoPHT1 expression in both Arabidopsis thaliana and D. officinale, whereas DoPIF5 inhibited these processes. In conclusion, the DoHY5/DoPIF5-DoPHT1 module mediates the red-light regulation of phosphorus uptake, providing a theoretical foundation for improving the cultivation and quality of D. officinale.

Bovine lactoferrin (bLf) is an essential additive in infant formula, with its bioactivity closely related to N-glycosylation. Currently, the production cost of lactoferrin remains high. This study compared eight ion-exchange resins and identified DoWex and 732 as optimal for bLf purification. Yields reached 4.46% for DoWex and 5.25% for 732, with purities exceeding 85% for both resins. Isomer-specific N-glycan analysis using HILIC-MS/MS revealed 58 distinct N-glycans in mature bLf, including 28 neutral and 30 acidic glycans, with the acidic N-glycans predominantly modified by α2,6-linked Neu5Ac. The bLf prepared by 732 resin shared >97% of the neutral and >93% of the acidic glycans with that of DoWex. Notably, the price of 732 resin is only one-18th that of DoWex, representing a significant reduction in production costs and making it promising in future large-scale manufacturing. This work facilitates efficient lactoferrin production and provides further studies on the relationships between glycans and their functions.