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PubMed2026

Deciphering S-nitrosylation-regulated metabolic networks in postmortem beef based on label-free modificomics: Identification of ferroptosis as a novel quality-related pathway.

This study elucidated the molecular mechanisms of S-nitrosylation on postmortem beef metabolism and quality based on the label-free modificomics. Varying degrees of S-nitrosylation were exogenously induced in beef semimembranosus (SM) muscle. Results indicated that a high S-nitrosylation level significantly increased beef pH and Warner-Bratzler shear force (WBSF) while reducing centrifugal loss (P < 0.05). A total of 828 S-nitrosylated proteins and 1458 modification sites were identified, of which 114 sites on 81 proteins (DSNPs) exhibited differential modification abundance, representing an increase of 125% compared with previous proteomics studies. DSNPs were mainly involved in glycolysis, the tricarboxylic acid cycle, oxidative phosphorylation, calcium signaling, cell structure, and ferroptosis. Notably, this study provides the first evidence in postmortem muscle that S-nitrosylation regulates key ferroptosis-related proteins, including ACSL, CP, and TF, offering new insights into the link between S-nitrosylation and the ferroptosis pathway in meat. Correlation analysis demonstrated that TF was significantly negatively correlated with pH and WBSF, but positively correlated with centrifugal loss (P < 0.05). Collectively, protein S-nitrosylation critically modulates postmortem beef quality through the coordinated regulation of multiple metabolic processes. More importantly, the identification of ferroptosis as a S-nitrosylation-sensitive pathway provides a new perspective for regulating meat quality through protein post-translational modifications.

Animals↗

PubMed2026

Mitigating pH-induced instability in deruxtecan-based ADCs: an onboard-mixing icIEF approach for robust charge heterogeneity characterization.

Accurate charge variant analysis of antibody-drug conjugates (ADCs) is essential for understanding product heterogeneity and ensuring quality control. However, Deruxtecan (DXd)-based ADCs present a unique analytical challenge due to the intrinsic instability of the payload, where the lactone ring readily undergoes hydrolysis under alkaline conditions, resulting in time-dependent shifts in charge distribution during imaged capillary isoelectric focusing (icIEF). In this study, we describe the development of an onboard-mixing icIEF method designed to minimize pH-induced degradation during sample preparation. By separating ADC samples from carrier ampholytes (CAs) prior to injection and enabling real-time mixing within the instrument, this approach effectively suppresses premature lactone ring opening and stabilizes charge variant profiles. Comparative studies between conventional premixing and onboard-mixing approach demonstrated that the latter significantly enhances reproducibility, particularly for acidic variants that are highly sensitive to structural conversion. Comprehensive method validation confirmed excellent precision, linearity, and sensitivity, with consistent performance across run-to-run and intra-day analyses. The results underscore the importance of controlling microenvironmental pH exposure in the analysis of chemically instable ADCs. The proposed onboard-mixing strategy provides a robust and efficient solution for icIEF-based characterization, reducing analytical artifacts while simplifying method development. This approach is broadly applicable to ADCs and other biotherapeutics containing pH-sensitive functional groups.

Hydrogen-Ion Concentration↗

PubMed2026

Divergent responses of the gill, hepatopancreas, and eyestalk to acute alkalinity stress in Penaeus vannamei: Osmoregulatory compromise, metabolic trade-off, and endocrine disruption.

The expansion of aquaculture into inland saline-alkali waters is constrained by high carbonate alkalinity (CA), a severe environmental stressor for crustaceans. However, the systemic molecular mechanisms underlying its lethal toxicity remain poorly understood. In this study, we employed a comparative transcriptomic approach to investigate the tissue-specific responses of Pacific white shrimp, Penaeus vannamei, under acute lethal stress (48 h-LC50). We focused on three functionally distinct organs: the gill, hepatopancreas, and eyestalk. The results revealed a systemic but highly tissue-specific transcriptomic response. The gill, as the primary interface, exhibited severe structural impairment and critical failure of osmoregulation, highlighted by the significant downregulation of delta-1-pyrroline-5-carboxylate synthetase (P5CS). In contrast, the hepatopancreas initiates a profound metabolic trade-off, sacrificing growth-related pathways to bolster a robust antioxidant defense system, as evidenced by the activation of sulfur metabolism and high protein turnover. The eyestalk displayed a striking disconnect between hyperactivated stress signaling pathways (e.g., mTOR/FoxO) and the collapse of its protein secretory machinery, marked by the suppression of the ER translocon component Sec61. Collectively, our findings suggest that lethal alkalinity toxicity in P. vannamei results from systemic collapse driven by a complex interplay of osmoregulatory failure, metabolic trade-offs, and endocrine disruption. This study provides a comprehensive molecular snapshot of an organism at its physiological limit, offering novel insights into the adaptive strategies and ultimate tolerance boundaries of crustaceans in extreme environments.

Animals↗

PubMed2026

Proteomic characterization of the acquired enamel pellicle under acidic challenges at early and mature formation stages.

OBJECTIVES: This study aimed to characterize acquired enamel pellicle (AEP) proteomic changes after exposure to citric acid (CA) and hydrochloric acid (HCl) under different pellicle formation times (3 and 120 min) in the same volunteers. DESIGN: Nine healthy volunteers participated in this randomized crossover in vivo study. The AEP was allowed to form for 3 or 120 min and subsequently exposed for 10 s to deionized water (control), 1% CA (pH 2.5), or 0.01 M HCl (pH 2.0). Pellicle samples were collected, followed by protein extraction, tryptic digestion, and analysis by nanoliquid chromatography (nanoLC) coupled to mass spectrometry (MS) with MSE (data-independent acquisition; nanoLC-MSᴱ). Label-free quantitative proteomics were performed for relative quantification using t-test (p < 0.05). RESULTS: At 120 min, CA exposure markedly reduced several typical AEP proteins, especially acidic proline-rich proteins (PRPs). Conversely, basic PRPs were upregulated, suggesting acid-resistance protein signature. At 3 min, basal-layer proteins (PRPs, cystatins, histatins and mucins) were more abundant. Hemoglobins increased 6-8-fold (up to 150-fold in 3 min control), suggesting association with early pellicle formation and an acid-resistant protein signature. CA exposures for 120 min also upregulated typical AEP proteins (PRPs, mucins, cystatins, immunoglobulins), while HCl exposure depleted albumins and lactotransferrin. CONCLUSION: Intrinsic and extrinsic acids induce distinct proteomic signatures in the AEP. Hemoglobin and PRPs appear consistently enriched in the early pellicle layer, reflecting an initial acid-resistant protein signature. These findings provide new insights into the molecular remodeling of the AEP following intrinsic and extrinsic acid exposure, highlighting proteins potentially involved in early-stage pellicle formation.

Humans↗

PubMed2026

Safety, tolerability, pharmacokinetics, and pharmacodynamics of oral JMKX003002 in Chinese healthy participants: a randomized, double-blind, placebo-controlled, single- and multiple-ascending dose, and food-effect phase I clinical trial.

OBJECTIVE: To evaluate the safety, tolerability, pharmacokinetics (PK), and pharma-codynamics (PD) of the sodium-hydrogen exchanger 3 (NHE3) inhibitor JMKX003002 in Chinese healthy participants. PATIENTS AND METHODS: This phase I, randomized, double-blind, placebo-controlled study included a single-ascending dose (SAD) study with seven cohorts (1 mg [n = 4] and 5, 20, 50, 75, 100, or 125 mg [n = 8]), a food-effect (FE) study with six sequence groups (25 mg twice daily, n = 4), and a multiple-ascending dose (MAD) study with two cohorts (10 mg or 20 mg twice daily, n = 10). RESULTS: JMKX003002 was well-tolerated, with mostly mild treatment-related adverse events. One Grade 3 diarrhoea occurred in each of the 50 mg and 125 mg groups. No serious adverse events were reported, and no participants discontinued or withdrew due to treatment-emergent adverse events. Most plasma samples were below the limit of quantification (0.2 ng/mL), with only transient detection of low concentrations, indicating low systemic exposure. JMKX003002 was primarily excreted in stool (79.9% recovered) and was undetectable in urine. The PD results consistently showed decreased urinary sodium and phosphorus, along with increased stool sodium and phosphorus, compared to baseline across all three studies. One day after discontinuation, stool sodium and phosphorus remained elevated relative to baseline in the MAD study. Mixed-effects model analysis in the FE study demonstrated significant food effect on stool sodium and phosphorus excretion. CONCLUSION: JMKX003002 exhibited favorable safety and tolerability with minimal systemic exposure. It effectively increased sodium and phosphorus excretion in stool. These promising findings warrant further investigation of JMKX003002 to evaluate its clinical benefits. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2300070473). Registered on April 13, 2023; prospectively registered.

Adult↗

PubMed2026

Low-salinity stress alters growth, histology, physiology, and transcriptomic profiles of the gills and antennal glands in Macrobrachium rosenbergii.

Salinity is a major abiotic constraint in freshwater aquaculture of the giant freshwater prawn Macrobrachium rosenbergii, yet the coordinated roles of the gills and antennal glands, the two primary osmoregulatory organs in decapod crustaceans, under low-salinity stress remain poorly characterized. Here, we integrated histological, physiological, and transcriptomic analyses to characterize the adaptive responses of M. rosenbergii to acute (96 h) and chronic (8 weeks) exposure to salinity 5. Chronic low-salinity stress significantly impaired growth performance and decreased the survival rate. Acute stress induced thinning of the gill filaments, partial disorganization of pillar cells, and dilation of the intermicrovillar space in the antennal glands, whereas chronic stress caused gill vacuolization, cuticle thinning, and adaptive folding of antennal gland microvilli. In parallel, acute exposure significantly decreased hemolymph sodium and potassium ion concentrations but increased magnesium ion concentration, whereas chronic exposure increased hemolymph sodium and potassium ion concentrations, upregulated gill Na+/K+-ATPase activity, and enhanced hepatopancreatic antioxidant capacity. Transcriptomic analyses revealed distinct tissue-specific responses. Under acute stress, the gills preferentially activated pathways associated with cytoskeletal remodeling, motor proteins, and tight junctions, whereas chronic acclimation shifted the transcriptional response toward the renin-angiotensin system and glutathione metabolism. In the antennal glands, acute stress rapidly activated the renin secretion pathway, whereas chronic exposure promoted membrane remodeling by enriching pathways related to lipid and glycan metabolism. These findings reveal tissue-specific functional differentiation and synergistic coordination between the gills and antennal glands that underpin M. rosenbergii's adaptive response to low-salinity stress.

Animals↗

PubMed2026

Thermal analysis techniques for microplastic mass quantification: Methodological challenges and standardization needs.

Microplastics (MPs, 1 μm-5 mm) and nanoplastics (NPs, <1 μm) are ubiquitous contaminants requiring standardized quantification methods. This systematic review evaluates thermal analysis techniques for mass-based MP detection, including pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), thermogravimetry-MS (TGA-MS), thermal extraction desorption-GC-MS (TED-GC-MS), and differential scanning calorimetry (DSC). Database searches (Web of Science, from inception to December 1, 2025) following PRISMA guidelines identified studies across seven environmental matrices (water, soil/sediment, atmosphere, biota, human tissues). We identify critical standardization gaps: inconsistent marker ion selection, unvalidated conversion factors for tire and road wear particles (TRWPs), and the absence of certified reference materials for complex matrices. Py-GC-MS demonstrates versatility but suffers from lipid interference in biological samples; TED-GC-MS offers superior sensitivity (sample capacity ∼200× Py-GC-MS) but lacks real-time chromatographic monitoring. To advance data comparability, we propose: (i) harmonized ion selection hierarchies based on specificity-sensitivity balance, (ii) matrix-specific TRWP quantification protocols, and (iii) inter-laboratory validation using environmental reference materials. This review provides a methodological roadmap for standardizing thermal analysis in MP research.

Humans↗

PubMed2026

Hydrogen-rich water combined with traditional Chinese medicine compound in the treatment of kidney stones: a randomized controlled prospective clinical trial.

JOURNAL/mgres/04.03/01612956-202701000-00009/figure1/v/2026-09-13T085902Z/r/image-tiff The formation and development of kidney stones are related to abnormal urine metabolism, oxidative stress and inflammation. Hydrogen-rich water has clear efficacy in antioxidant and improving inflammatory status, while Ye-Shi-Shi-Lin-Formula is a clinically effective traditional Chinese medicine compound preparation for treating kidney stones. This randomized controlled prospective clinical trial from July 2025 to March 2026 at the Seventh People's Hospital Affiliated to Shanghai University of Traditional Chinese Medicine examined the effect of hydrogen-rich water and Ye-Shi-Shi-Lin-Formula on kidney stones. The included 100 patients with kidney stones were randomly divided into blank, hydrogen-rich water, hydrogen-rich water and Chinese medicine, and Chinese medicines groups. The patients received drinking hydrogen-rich water and/or Ye-Shi-Shi-Lin-Formula daily for 12 weeks. All subjects received basic treatment following the guidelines. Imaging examination, urine metabolism testing, renal function, inflammation and oxidative stress index, blood routine and liver function are used to detect the efficacy and safety of hydrogen-rich water and Ye-Shi-Shi-Lin-Formula. Results showed that the total effective rate of kidney stone treatment in blank group, Chinese medicines group, hydrogen-rich water and Chinese medicine group and hydrogen-rich water group was 28%, 76%, 80% and 32%. The Ye-Shi-Shi-Lin-Formula can partially alleviate the oxidative stress, uric acid metabolism and urinary magnesium levels of patients with kidney stone and improve the function of renal tubules. The hydrogen-rich water therapy showed only efficacy in improving glutathione reductase but the combination of hydrogen-rich water and Ye-Shi-Shi-Lin-Formula has shown superior efficacy in improving oxidative stress and related metabolic factors of blood uric acid and urine stones, as well as in renal tubular function. The results indicate that the addition of hydrogen-rich water can improve urinary metabolism and oxidative stress status in the treatment of kidney stones with Ye-Shi-Shi-Lin-Formula. The study was registered at the International Traditional Medicine Clinical Trial Registry (Registration No. ITMCTR2025001446).

Humans↗

PubMed2026

Enhancement of secondary organic aerosol formation from isoprene photooxidation by ammonia.

Ammonia (NH3) can participate in atmospheric secondary organic aerosol (SOA) formation by reacting with organic acids and carbonyl compounds in particle phase, but its influence on the gas phase chemistry remains unclear. This study performed a series of smog chamber experiments to investigate the influence of NH3 on the formation of SOA from isoprene photooxidation by OH radicals. Both gas and particle phase products were measured with a series of state-of- art instruments including a nitrate ion chemical ionization mass spectrometer (nitrate-CIMS) and high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS). Our results showed that in the presence of NH3 SOA in the chamber significantly increased, along with an enhanced oxidation of isoprene. CIMS analysis further showed that NH3 in the chamber homogeneously reacts not only with gas-phase organic acids but also with gaseous low volatility oxygenated organic molecules (OOMs) to generate extremely low volatility and ultralow volatility NH3-OOMs clusters. Quantum chemical calculation showed that NH3 can spontaneously interact with OOMs to form NH3-OOMs clusters by forming hydrogen bonds with RCOOH, R-OOH, and R-OH. These clusters can promote new particles formation and particle growth through nucleation and condensation, directly enhancing the isoprene SOA production with a contribution of 78% to the enhanced SOA. Moreover, the formation of NH3-OOMs clusters also results in more isoprene consumed by OH radicals, indirectly increasing the SOA production with a contribution of 22 % to the enhanced SOA. Our work for the first time clarified a synergetic effect of NH3 on isoprene SOA formation, which should be accounted for by models.

Aerosols↗

PubMed2026

Cross-kingdom dynamics of the subgingival bacteriome and mycobiome: A pilot study on the effects of a novel HA-H₂O₂-Glycine formulation to treat periodontitis.

OBJECTIVES: Traditional periodontal therapy primarily focuses on bacterial biofilm control; however, recent evidence also suggests a critical role for the oral mycobiome. This study evaluated the clinical and ecological impact of a novel mouthwash formulation containing hyaluronic acid (HA), hydrogen peroxide (H2O2), and glycine on periodontal patients METHODS: This prospective, randomized split-mouth trial included 13 adult participants with periodontitis treated with HA-H2O2-glycine formula (BMG0703A) used twice a day for seven days. Subgingival plaque samples were collected from periodontal pocket and healthy control sites at baseline (T0) and one-week post-treatment (T1). Microbial and fungal communities were characterized using Next-Generation Sequencing (NGS) of the 16S rRNA and ITS2 regions. Linear Mixed Models (LMM) and Spearman correlation were used to assess taxonomic shifts and cross-kingdom relationships. RESULTS: Sequencing revealed a promising ecological shift: the bacteriome shifted from anaerobic dominance (Olsenella, Peptostreptococcus) toward a health-associated aerobic profile, with Rothia near-doubling (11.91% to 22.68%). The mycobiome underwent a "normalization" effect: Candida abundance decreased significantly (22.8% to 9.1%), while fungal Shannon diversity in pockets returned to healthy-site levels. Inter-kingdom analysis identified antagonistic relationships between expanding commensal bacteria and opportunistic fungi, suggesting that the intervention may help re-establish a protective bacterial niche. CONCLUSIONS: The HA-H2O2-glycine formulation seems to facilitate a rapid, cross-kingdom modulation of the subgingival niche. By reducing anaerobic pathogens and normalizing the mycobiome it appear to induce short-term changes, suggesting potential as adjunctive strategy in periodontal management. CLINICAL SIGNIFICANCE: The present work underlines the possible cross-Kingdom effects of a novel compound.

Humans↗

PubMed2026

Utero-placental calcium and magnesium ion channels: A systematic review of obstetric implications of their alterations.

Despite the established roles of calcium (Ca2+) and magnesium (Mg2+) in placental function and uterine contractility, limited information exists on how dysregulation of major ion channels contributes to poor pregnancy outcomes. We synthesized data on the consequences of Ca2+ and Mg2+ channelopathies in uterine and placental functions. Using PubMed, Wiley Online, AJOL, and Web of Science databases for article search, a systematic review of forty-nine papers published between 2000 and March 2026 was carried out and reported in accordance with the PRISMA 2020 guideline. Based on the PICO framework, eligible studies involving human, animal, and in vitro designs were chosen and subjected to narrative analysis. L-type and T-type voltage-gated Ca2+ channels, together with transient receptor potential channels, emerged as principal mediators of placental Ca2+ transport and myometrial contractility. Mechanosensitive Piezo1 channels mediate stretch-activated Ca2+ influx, while store-operated Ca2+ entry pathways involving STIM1-Orai1 sustain intracellular Ca2+ homeostasis. Potassium-Ca2+ coupling channels modulated membrane hyperpolarization and anti-labor effects, and intracellular regulators such as PMCA and RYR1 fine-tuned Ca2+ homeostasis. The Mg2+ transporters are essential for preserving Mg2+ homeostasis and regulating Ca2+-dependent excitability. Dysregulation of these ion channel systems was consistently linked to abnormal uterine contractility, preterm birth, preeclampsia, fetal growth restriction, and adverse pregnancy outcomes. Both Ca2+ and Mg2+ ion channelopathies represent both a potential therapeutic target and a mechanistic factor underlying key obstetric complications.

Female↗

PubMed2026

Three-dimensional porous nano-hydroxyapatite@gelatin composite as efficient adsorbent for uranyl ion removal from low-level radioactive wastewater.

The contamination of water resources by uranyl (UO22+) ions poses significant environmental and health risks, requiring the development of efficient and sustainable remediation strategies. Adsorption-based techniques have emerged as promising approaches in the field of UO22+ removal, but the design of cost-effective, high-capacity, and environmentally friendly adsorbents remains challenging. In this study, a three-dimensional porous nano-hydroxyapatite@gelatin (nHAP@Ge) composite was synthesized through glutaraldehyde cross-linking, combining the structural stability of Ge with the high uranium affinity of nHAP. The optimized nHAP@Ge, with a nHAP:Ge mass ratio of 1:0.5, exhibited exceptional UO22+ removal efficiency (97 %), along with high adsorption capacity (364.03 mg/g). Systematic characterizations using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) methods revealed that the porous structure and surface functional groups (-OH, Ca2+, and PO43-) of the material synergistically contributed to binding UO22+ species. Furthermore, the incorporation of nHAP into the Ge framework resulted in enhanced thermal stability while significantly improving the UO22+ adsorption performance. This work presents a scalable, eco-friendly, and recyclable strategy for the effective treatment of uranium-contaminated water, with potential applications in nuclear wastewater treatment and environmental remediation.

Adsorption↗

PubMed2026

Viral replication through phase separation: Cytosolic and nuclear condensates.

Replication of many RNA and DNA viruses occurs within specialized intracellular hubs organized as membraneless biomolecular condensates (BCs) driven by liquid-liquid phase separation. As obligate intracellular parasites, viruses depend on the host cell machinery to complete their replication cycles and therefore actively remodel the intracellular environment to favor viral genome replication, transcription, and assembly. Cytosolic and nuclear phase-separated replication compartments (RC) provide concentrated and dynamic platforms that promote efficient interactions between viral genomes and viral or host proteins essential for infection. The formation of viral replication BCs is typically facilitated by viral proteins enriched in intrinsically disordered regions and low-complexity domains, which enable multivalent interactions with viral nucleic acids and cellular factors. These interactions are mediated by diverse biophysical forces, including hydrophobic and π interactions, hydrogen bonding, molecular crowding, and osmotic effects. Throughout infection, viral BCs remain highly dynamic, allowing continuous exchange of components and functional maturation of replication hubs. Their properties and activities are further regulated by post-translational modifications of viral and host proteins, such as phosphorylation, acetylation, and methylation. In this review, we summarize current evidence supporting liquid-liquid phase separation as a central organizing principle of viral RCs. We focus on representative RNA and DNA viruses that replicate in the cytosol or nucleus, highlighting virus-specific strategies, conserved mechanisms, and the consequences of BC formation for viral replication efficiency, host antiviral responses, and therapeutic intervention.

Phase Separation↗

PubMed2026

Selective and sensitive colorimetric sensing of carbosulfan based on BiO2-x/Bi2O2.75 nanosheets with excellent haloperoxidase-like activity.

The development of colorimetric methods based on directly inhibiting nanozyme activity for pesticide detection has attracted considerable attention. In this study, we report a novel colorimetric sensing strategy utilizing BiO2-x/Bi2O2.75 nanosheets (BiO2-x/Bi2O2.75 NSs) with haloperoxidase (HPO)-like activity for the rapid and sensitive detection of carbosulfan (CBS) in foods. Oxygen-vacancy-rich BiO2-x/Bi2O2.75 NSs with HPO-like activity were rationally constructed. Kinetic studies revealed a remarkable Michaelis-Menten constant (Km) of 0.014 mM for I-, indicating a higher affinity for iodide ions than other reported HPO-like nanozymes, as evidenced by its lower Km. Under acidic conditions, CBS tends to be hydrolyzed to produce reductive sulfide species, which directly inhibit the iodoperoxidase-like activity of BiO2-x/Bi2O2.75 NSs, enabling selective detection with a limit of detection (LOD) of 0.18 μg/mL and a linear range of 0.20-100 μg/mL. When the concentration of interfering pesticides and substances was 5 times that of CBS, the sensor remained unaffected, exhibiting excellent stability and specificity. This work contributes to the detection of CBS in complex food matrices, bridging the application gap of HPO-like nanozymes in pesticide detection and providing a promising method for food safety detection.

Colorimetry↗

PubMed2026

The composition of the periostracum in the razor clam Sinonovacula constricta and the mantle's response to sulfide.

The razor clam Sinonovacula constricta inhabits sulfide-rich intertidal sediments and exhibits remarkable tolerance to this toxicant, yet the role of its periostracum in sulfide adaptation remains poorly understood. In this study, we investigated the composition and structure of the periostracum proteins, and the response of the mantle to sulfide stress. Scanning electron microscopy and energy-dispersive X-ray spectroscopy revealed that the periostracum is approximately 10 μm thick and contains 1.43 wt% sulfur, and proteomic analysis further confirmed the presence of organic sulfur (Cys/Met-rich proteins), suggesting its involvement in sulfur deposition. Using LC-MS/MS, we identified 77 high-confidence proteins from the periostracum, which were classified into six functional categories: enzymes, framework proteins, immune-related proteins, calcium ion-related proteins, other proteins, and proteins with unknown functions. Phylogenetic analyses of representative proteins revealed bivalve-specific evolutionary patterns, with several proteins exclusively present in Bivalvia, such as Unknown protein 2 and 7, which possess signal peptides and low-complexity domains. For the sulfide exposure experiment, razor clams were subjected to three Na2S concentrations (0, 10, and 100 μM). qPCR analysis showed that, compared with the control group, Chitin-binding protein 3 and Tyrosinase were significantly upregulated in the mantle, peaking in the 100 μM group at 48 h (5677.84-fold and 157.20-fold, respectively), whereas Collagen and Cadherin 3 were generally suppressed. This study represents one of the most comprehensive proteomic profiles of the razor clam periostracum and highlights the mantle's potential role in sulfide tolerance, offering insights for sulfur-tolerant aquaculture breeding and bioremediation applications.

Animals↗

PubMed2026

Improved comprehensive profiling of fecal bile acids through chemical derivatization combined with HPLC-MS/MS analysis.

Bile acids (BAs) facilitate the digestion and absorption of fats and influence lipid and glucose homeostasis, making them potential therapeutic targets for obesity and related metabolic disorders. The liver and intestinal microbiota modify BAs structurally, generating diverse chemical forms and isomers. Comprehensive profiling of the BA pool is critical for understanding their key biological functions and as a therapeutic approach for related diseases. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) is usually chosen as the preferred method for BA detection due to the complex chemical structures, the wide range of actual concentrations and the complexity of fecal sample matrices. However, free BAs are difficult to ionize, resulting in low detection signals and a lack of characteristic structural fragments to assist in structural identification. In this method, the labeling reagent (2-aminoethyl) trimethylammonium (AETMA) is employed to label the carboxyl group of BAs. Compared with underivatized BAs, the detection sensitivity of unconjugated BAs was enhanced by 25-180 fold, while that of conjugated BAs increased by 6-160 fold. It also generates unique fragment ions and enhances MS response, facilitating the discovery of potential BAs. Methodological parameters were validated using 38 BAs as representatives. Through methodological validation, it was verified that the precision, recovery, matrix effect and stability parameters of the method met acceptable criteria. We also identified 61 confirmed BAs and 55 additional candidate BAs in human pooled fecal samples. It has been successfully applied to fecal BA analysis in obese populations, providing valuable insights into potential therapeutic strategies for obesity.

Tandem Mass Spectrometry↗

PubMed2026

Unveiling the molecular basis of gonadal development: Multi-omics uncovers sex-related genes and steroid pathways in Sinonovacula constricta.

The razor clam Sinonovacula constricta is an economically important cultured mollusk in China, but the molecular mechanism of its gonadal development and sexual differentiation remains unclear. This study integrated gonadal transcriptomic, proteomic, and metabolomic analysis to identify key sex-related molecules. Transcriptome analysis identified 2795 DELs and 6497 DEGs between sexes, including the sex-related genes Fem-1b, Fem-1c, GUCY1B2 and FAT4, as well as a regulatory network of 39 lncRNA-mRNA pairs involving Tektin-4, Ropporin-1, Histone H1, and FoxN4. Proteomic analysis revealed 3217 DEPs: Tektin family members, Ropporin-1 and Tssk proteins were upregulated in the testis, while histone H1 and FAT4 were upregulated in the ovary. Metabolomic analysis detected 409 DEMs, with uridine identified as a potential sex differential marker (upregulated in the ovary), and 23 gonadal development-related DEMs showed sex-specific upregulation. Integrative transcriptome-proteome analysis identified 1543 co-expressed DEGs/DEPs enriched in nucleosome assembly, oxidative phosphorylation, and carbon metabolism, including key sex-related genes AKAP14, Tektin/Tssk families, Histone H1, and FAT4. Transcriptome-metabolome integration identified 32 shared KEGG pathways (e.g., biosynthesis of unsaturated fatty acids, pyrimidine metabolism), while proteome-metabolome integration revealed 5 (positive ion) and 6 (negative ion) co-enriched pathways, with alanine, aspartate and glutamate metabolism and oxidative phosphorylation being functionally relevant to gonadal development. Collectively, these results reveal the molecular basis of gonadal development, highlight critical sex-related genes and steroid metabolic pathways, and provide valuable resources for future reproduction and breeding in S. constricta.

Animals↗

PubMed2026

Desert-derived Ensifer sp. SA403 enhances potato salt tolerance by reshaping rhizosphere microbiome functions and host responses.

Soil salinization increasingly threatens global food security, and potato (Solanum tuberosum L.), a moderately salt-sensitive crop, is particularly vulnerable to saline soils. Plant growth-promoting rhizobacteria (PGPR) offer a promising strategy to improve crop performance, yet how PGPR interact with native microorganisms to enhance potato salt tolerance remains poorly understood. In this study, we identified a desert-derived PGPR strain, Ensifer sp. SA403, which substantially enhanced potato performance under high salinity across sterile, non-sterile and field conditions. Physiologically, inoculation with SA403 reduced shoot Na⁺ accumulation and increased the K⁺/Na⁺ ratio; notably, these effects were markedly stronger in non-sterile substrates than under sterile conditions, indicating that SA403-mediated ion homeostasis relies on cooperation with the resident microbiota rather than on the strain acting alone. Metagenomic profiling indicated that SA403 strain reshaped rhizosphere communities, significantly enriching beneficial taxa such as Priestia and Bradyrhizobium, and upregulated functional pathways involved in glutathione and sulfur metabolism. Furthermore, host transcriptomic analyses showed that SA403 modulated plant responses to salt stress, with differentially expressed genes enriched in jasmonic acid signaling, ethanolamine metabolism and amino-acid biosynthesis pathways. Field trials on saline soils confirmed that SA403 significantly increased seedling emergence and tuber weight. Together, our results demonstrate that SA403 functions as a biological mediator that optimizes rhizosphere microecology and coordinates ion balance and host signaling to enhance potato salt tolerance. These findings support the potential of SA403 as a robust PGPR-based tool for sustainable potato production on saline soils.

Rhizosphere↗