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New insights into soil amendment: Impact of humic acid on typical antibiotic resistance in agricultural soil.

Humic acid (HA) addition can improve agricultural soil, but little is known about how it affects the soil resistome. In this study, we used selective agar plate combined with quantitative PCR (qPCR) and 16S rRNA gene sequencing to investigate how HA influences antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARGs) in soil contaminated with erythromycin and kanamycin. 0.1 % HA reduced the abundance of culturable erythromycin-resistant bacteria (ERB), while promoting the growth of kanamycin-resistant bacteria (KRB). Lysinibacillus and Paenibacillus were the dominant genera in ERB and KRB, respectively, governing the changes in their abundances. At this concentration, the Lysinibacillus abundance in ERB decreased from 96.74 % to 70.57 %. Meanwhile, that of Paenibacillus in KRB increased from 33.40 % to 77.44 %. The copy number of ermF decreased after HA addition, while that of ermB increased. Furthermore, 0.1 % HA significantly reduced the copy number and relative abundance of aadA1 and aac(6')-Ib (aka aacA4)-03 in the soil. Changes in these two types of ARB and ARGs were primarily driven by shifts in the microbial community structure. Soil physicochemical properties, particularly increased organic matter (OM), altered the absolute abundance of ermB. Meanwhile, changes in intI1 abundance determined the risk associated with aadA1 and aac(6')-Ib (aka aacA4)-03. These findings emphasize the dual role of HA in the dissemination of antibiotic resistance in agricultural soils and highlight the necessity of considering dose-dependent effects when applying HA as a soil amendment.

Soil Microbiology

A Novel Moisturizer Formulated With Micronized Centella asiatica and Mandelic Acid Improves Mature, Crepey Skin.

BACKGROUND: Dermatoporosis is a condition of fragile, aging skin that manifests as altered pH, wrinkles, laxity, easy bruising, and hyperpigmentation. This study evaluated efficacy, safety, and subject perception after the use of a novel cream, GC (Galderma Laboratories, LP, Fort Worth, TX), on subjects with mature, aging skin. METHODS: A 12-week multicenter, randomized, blinded, in-use study enrolled female and male subjects aged 40 to 60 years of all races, ethnicities, and Fitzpatrick skin types. Subjects were required to have a history of fragile skin and dry, crepey skin on the knees and thighs. GC cream was applied to knee and upper thigh skin twice daily. Assessments included clinical grading, digital photography, bioinstrumentation (skin texture, pH, and heatmap hydration), standard safety assessments, and satisfaction. RESULTS: Use of GC cream for 12 weeks resulted in significant improvements in skin crepiness, photodamage, and firmness, as well as decreased skin pH and early improvements in skin roughness and smoothness from baseline. Corneometer heatmapping documented improved skin hydration over baseline. No adverse events were reported; the GC cream was well tolerated, and subjects reported high satisfaction. CONCLUSION: Twice-daily application of the novel GC skin cream significantly improved the overall skin quality of mature, aging skin, including crepiness, photodamage, firmness, texture, pH, and hydration. GC cream was well tolerated with high subject satisfaction. These data are intended to help guide healthcare providers and patients in choosing an effective moisturizer that was specifically designed for patients with fragile, mature skin.

Humans

Fructophilic lactic acid bacteria as a window into multi-scale convergent evolution.

Fructophilic lactic acid bacteria (FLAB) are a group of lactic acid bacteria with unique growth characteristics, that is, poor growth on glucose. Their growth is enhanced in the presence of fructose or external electron acceptors. These organisms inhabit fructose-rich environments such as flowers, fruits, and pollinating insects, particularly honey bees. Apilactobacillus spp. and Fructobacillus spp. are representatives of FLAB, although they belong to phylogenetically distant clades. These organisms commonly possess markedly small genomes with a low number of coding DNA sequences. Furthermore, their genomes are characterized by a markedly reduced number of genes involved in carbohydrate transport and metabolism. Genome reduction in FLAB reflects convergent adaptation to fructose-rich environments rather than general genome streamlining. The two distinct FLAB genera, Fructobacillus and Apilactobacillus, independently lost more than 100 genes in statistically similar orders. In contrast, genes involved in carbohydrate and amino acid metabolism exhibited reversed orders of loss between the two genera. Furthermore, FLAB genomes lack an intact bifunctional alcohol/aldehyde dehydrogenase gene (adhE), which causes their poor growth on glucose. A comparative genomic study suggested the evolutionary process underlying adhE gene decay during adaptation to the fructose-rich environments, including pollinating insects. In conclusion, FLAB represent a unique example of habitat-driven convergent reductive evolution that can be investigated across multiple biological scales - from individual genes to whole genomes - in the diverse LAB group with a wide range of habitats, and partially share the fructophilic evolution with eukaryotic yeasts found in fructose-rich habitats.

Fructose

Effect of flavored on!® nicotine pouch products on smoking behaviors: A sequential, multiple assignment, randomized controlled trial.

PURPOSE: To evaluate whether flavored versus unflavored nicotine pouch (NP) access affects cigarette reduction and smoke exposure among adults who smoke daily, and whether delayed flavor introduction affects these outcomes. METHODS: Adults who smoked ≥ 5 cigarettes/day (CPD) with interest in replacing cigarettes with NPs were enrolled in a remote, six-week, sequential multiple assignment randomized trial (n = 402 randomized; n = 400 analyzed). Participants were randomized to immediate access to seven NP flavors (Flavor), unflavored-only access for six weeks (Original), or unflavored-only for three weeks followed by flavor access (Delayed Flavor). Primary outcomes were ≥ 50% reduction in weekly mean expired-air carbon monoxide (CO) from baseline and mean CO at Week 6. Secondary outcomes included ≥ 50% CPD reduction, mean CPD, CO-verified 7-day abstinence, and incident smoke-free days. RESULTS: At Week 6, Flavor and Original did not differ in ≥ 50% CO reduction (14.3% vs 14.2%; IRR=1.0, 95% CI=0.6-1.8) or mean CO (18.3 vs 16.5 ppm; β=1.9, 95% CI=-1.3-5.0). CPD decreased across groups by Week 6, with no differences between Flavor and Original in ≥ 50% CPD reduction (50.3% vs 51.6%; IRR=1.0, 95% CI=0.8-1.2) or CO-verified abstinence (9.3% vs 8.9%; IRR=1.0, 95% CI=0.5-2.2). Flavor increased smoke-free days early, with attenuation over time. Among Week 3 non-responders, delayed flavor access increased ≥ 50% CPD reduction at Week 6 (33.3% vs 18.6%; IRR=1.8, 95% CI=1.0-3.2). CONCLUSIONS: NP access supported cigarette reduction regardless of flavor availability, but flavors may accelerate smoke-free days and improve response among individuals who do not reduce cigarette consumption with unflavored products alone.

Humans

Desmodium styracifolium Total Flavone Capsules for Urolithiasis: A Phase 3 Randomized Clinical Trial.

IMPORTANCE: No oral medication is currently approved for the management of urolithiasis. Guang Jing Qian Cao (Desmodium styracifolium total flavone capsules; hereinafter, Guang Jing), a traditional Chinese herbal extract, has shown clinical benefits for urolithiasis, but randomized clinical trials are needed to assess its effectiveness. OBJECTIVE: To evaluate whether Guang Jing improves stone passage rates (SPRs) compared with placebo in adults with urolithiasis. DESIGN, SETTING, AND PARTICIPANTS: This double-blind, placebo-controlled, phase 3 randomized clinical trial was conducted at 34 sites in China from December 2017 to April 2020. Participants included adults (aged 18-70 years) with diagnosed ureteral stones. Data analysis was conducted on November 4, 2020. INTERVENTION: Participants were randomized 3:1 to receive oral Guang Jing (0.6 g) or matching placebo 3 times daily for 28 days, in addition to investigator-prescribed background medication. MAIN OUTCOMES AND MEASURES: The primary outcome was SPR by day 28, confirmed by computed tomography. Secondary outcomes included SPR by day 14, stone migration rate, and stone migration distance. Between-group comparisons were performed using the Cochran-Mantel-Haenszel test for categorical outcomes and t tests for continuous outcomes. RESULTS: A total of 606 participants were randomly assigned to receive Guang Jing (n = 458) or placebo (n = 148). Their mean (SD) age was 43.0 (12.0) years, 474 (78.2%) were male, and the mean (SD) stone size was 0.6 (0.1) cm. The SPR by day 28 was significantly higher for the Guang Jing group compared with the placebo group (204 of 457 [44.6%] vs 50 of 148 [33.8%]; relative risk, 1.32 [95% CI, 1.03-1.69]; P = .03), with an absolute risk difference of 10.9 (95% CI, 2.0-19.7) percentage points. No significant between-group differences in SPR by day 14 (Guang Jing vs placebo: 133 [29.1%] vs 33 [22.3%]; P = .14) or stone migration distance (mean [SD], 29.5 [51.8] mm vs 29.7 [43.8] mm; P = .11) were observed. Adverse event rates were similar for the Guang Jing and placebo groups (88 [19.3%] vs 27 [18.2%]). CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, treatment with Guang Jing significantly increased the expulsion of 5- to 10-mm ureteral stones by day 28, with a favorable safety profile. These findings suggest that Guang Jing may be an additional medical expulsive therapy option for appropriately selected patients. TRIAL REGISTRATION: Chinese Clinical Trial Registry Identifier: ChiCTR-IIR-17013275.

Humans

Complete mitochondrial genomes of eight cyclophyllidean tapeworms: genome pattern and phylogenetic analysis.

Cyclophyllidean tapeworms are widespread parasites of significant medical and veterinary importance. However, mitochondrial (mt) genomic resources for cyclophyllideans from China, particularly those recovered from wildlife hosts, remain comparatively limited. In this study, we sequenced and characterized the complete mt genomes of eight cyclophyllidean isolates collected from diverse wild and domestic hosts in China, including two Hymenolepis sp. isolates and two Raillietina sp. isolates from China, and four additional isolates of previously sequenced Taenia species. The circular mt genomes ranged from 13,387 to 14,021 bp in length, encoding 36 typical genes with variable non-coding regions. Comparative analysis revealed highly conserved gene composition and mostly conserved mt architecture, with localized rearrangement patterns detected among the cyclophyllidean lineages examined. In particular, all sampled Taeniidae exhibited a consistent trnL1-trnS2 arrangement, whereas the examined non-Taeniidae families showed the trnS2-trnL1 arrangement, confirming and extending, across additional wildlife-associated isolates, a previously proposed family-associated gene-order marker within Cyclophyllidea. Phylogenetic analyses based on concatenated amino acid sequences of the 12 protein-coding genes placed the eight isolates within their expected families, in topologies broadly consistent with previous mitogenomic studies. These data provide additional Chinese mitogenomic references, especially for underrepresented wildlife-associated isolates, and support family-associated gene-order patterns in Cyclophyllidea.

Animals

Flavoromics-based profiling reveals taste and aroma differences between infant formula and breast milk.

Flavor differences between infant formula (IF) and breast milk (BM) are considered a potential factor affecting infants' acceptance of IF. This experiment employs flavoromics combined with multivariate statistical analysis to systematically compare the flavor profiles of IF and BM. Electronic tongue analysis and amino acid correlation revealed that IF was characterised by pronounced saltiness and umami richness, whereas BM exhibited greater bitterness and astringency. Volatile compound profiling identified five key flavor constituents in IF, predominantly aldehydes such as hexanal and pentanal. In contrast, BM contained a broader array of compounds-including acids, aldehydes, and esters-resulting in a more complex flavor profile. Kyoto Encyclopedia of Genes and Genomes (KEGG)-based metabolic pathway annotation, together with fatty acid profiling, suggested that some volatiles may be associated with lipid oxidation, Maillard reaction and sulfur-containing amino acid degradation pathways, offering a theoretical basis for the targeted optimisation of IF flavor.

Humans

Prognostic effect of serum glial fibrillary acidic protein and neurofilament light chain for predicting progression independent of relapse activity in multiple sclerosis: A systematic review.

BACKGROUND: Progression independent of relapse activity (PIRA) is increasingly appreciated as one of the important factors contributing to disability accumulation in MS. sGFAP and sNfL could represent markers reflecting two separate biological processes related to relapse-independent progression in MS. OBJECTIVE: To perform a systematic review of the literature on blood GFAP and/or NfL measured in relation to PIRA or other similar relapse-independent progression endpoints in people with MS. METHODS: PubMed, Scopus, and Web of Science databases were searched from inception to 1 June 2026. The eligible studies were original human studies measuring blood GFAP and/or NfL concentrations in serum, plasma, or any other type of blood-derived material and assessing PIRA, PIRMA, CDP/CDW without relapses, relapse-free EDSS progression, non-inflammatory progression, or comparable relapse-independent disability worsening outcomes. Methodological quality was assessed according to the Newcastle-Ottawa scale and the QUIPS instrument for bias detection in the body of evidence on prognostic factors. Due to heterogeneity of outcomes, biomarker measurements and effect estimates, results were synthesized qualitatively rather than quantitatively. RESULTS: After removing duplicates, 1206 records were screened, followed by full-text review of 120 reports. A total of 18 reports were included. Overall, sGFAP was associated more frequently with PIRA or PIRA-like disability progression, particularly in cohorts with suppressed or limited overt inflammatory activity. Evidence for sNfL was more variable and context-dependent: several studies reported associations with PIRA-like or relapse-independent disability worsening when acute inflammatory activity was absent, suppressed, or analytically separated, whereas other studies reported negative or inconclusive findings. Negative or inconclusive results were reported by several articles, particularly when broad outcomes were evaluated or the study population was small. CONCLUSION: Blood GFAP and NfL give complementary but non-interchangeable information concerning PIRA in MS patients. The existing evidence base does not allow us to perform meta-analysis because of heterogeneity in terms of outcomes, standardization of biomarkers, and treatment context. Further prospective investigations with uniform criteria will be necessary for their use as biomarkers of PIRA in clinical settings.

Humans

EDucation and eXercise for gluteal tendinopathy in an Irish context (EDX-Ireland): findings from the LEAP-Ireland feasibility randomised controlled trial.

OBJECTIVE: To assess feasibility of a randomised controlled trial (RCT) investigating effectiveness of 6 sessions of an EDucation and eXercise intervention delivered over 8 weeks (EDX-Ireland) for gluteal tendinopathy, against usual care. EDX-Ireland was modified from a 14-session EDucation and eXercise intervention (EDX), delivered over 8 weeks, previously evaluated in an Australian RCT. DESIGN: Feasibility parallel RCT. METHODS: Participants were randomly assigned to physiotherapist-led EDX-Ireland or usual care. EDX-Ireland comprised 6 sessions of education, hip abductor strengthening and functional loading over 8 weeks, supported by a home exercise programme. Primary outcomes included success of different recruitment strategies and recruitment/retention rates. Secondary outcomes measured global rating of change and other clinical outcomes. Descriptive statistics (percentage, mean, standard deviations and 95% confidence intervals (CI)) are presented. RESULTS: Of 323 individuals who expressed interest in study participation, 119 completed physical examination screening, and 65 met criteria and consented to participate (recruitment rate 55%). Sixty-five people (89% women; mean age 53.1 ± 9.3 years), were randomised to EDX-Ireland (n = 32) or usual care (n = 33). Eighty-three percent (n = 54) were recruited via social media/community, 3% (n = 2) from general practitioners and 14% (n = 9) from orthopaedic/rheumatology. Retention was 92% (95% CI 82-97%, n = 60) at 8-weeks, and 89% (95% CI 79-96%, n = 58) at 3-months. Feasibility thresholds were met. Effect size estimates indicate that 134 participants would be required for a future RCT. CONCLUSION: Pre-defined recruitment and retention thresholds were met, indicating that a RCT evaluating 6 sessions of physiotherapist-delivered education and exercise against usual care for gluteal tendinopathy is feasible. TRIAL REGISTRATION: Clinicaltrials.gov (NCT05516563).

Humans

Integrated phytochemical and bioactivity profiling of Xanthium strumarium fruits from Korea and China: Implications for origin-specific quality specification.

BACKGROUND: Geographic origin influences the phytochemical composition and biological activities of medicinal plant resources. Xanthium strumarium L. (XS) fruit is widely used in East Asian traditional medicine. However, current pharmacopeial standards primarily recognize Chinese-derived material, despite the availability and traditional use of XS in Korea. To address this gap and support origin-informed quality specification, we compared fruits from Korea (XS-K) and China (XS-C) using chloroplast genome sequencing, targeted phytochemical profiling (high-performance liquid chromatography (HPLC) for selected phenolics and gas chromatography-flame ionization detection (GC-FID) for fatty acids and phytosterols, and multivariate chemometric analysis. RESULTS: Chloroplast genome analysis revealed high overall similarity but localized divergence around the rpoC2 locus and a greater mutation burden in XS-C, supporting origin-associated genomic differentiation. Phytochemical profiling revealed distinct origin-dependent metabolic signatures. XS-K showed higher levels of phytosterols, chlorogenic acid, 4,5-dicaffeoylquinic acid (4,5-DCQ), and xanthatin was detected only in XS-K, whereas XS-C exhibited greater abundance of total fatty acids, particularly oleic acid. Unsupervised clustering and log2 fold-change ranking confirmed clear compositional separation, and variable importance in projection (VIP) analysis identified chlorogenic acid, β-sitosterol, oleic acid, 4,5-DCQ, and xanthatin as major discriminators between origins. Bioactivity assays demonstrated that XS-K exerted stronger antioxidant effects in ABTS, DPPH and FRAP assays, stronger skin-related enzyme inhibition, and greater antibacterial activity against Staphylococcus aureus, consistent with its enriched phenolic and sterol profile. CONCLUSION: Together, chloroplast sequence variation, targeted metabolite quantification, and screening bioassays consistently distinguished XS-K from XS-C. These findings support the use of candidate markers for the origin-based authentication and quality control of XS fruit-derived ingredients. © 2026 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Fruit

Integrated analysis uncovers exogenous induction and molecular regulation of erinacine A accumulation in Hericium erinaceus.

Erinacine A, a cyathane-type diterpenoid mainly from Hericium erinaceus mycelia, exhibits prominent neurotrophic and neuroprotective activities, making it a promising candidate for managing neurodegenerative diseases. However, its low abundance and unclear genetic regulatory mechanisms hinder its application as a nutraceutical. This study aimed to decipher its regulatory mechanisms and enhance production. Four exogenous inducers were screened, with salicylic acid (SA) and ergosterol (ERG) significantly increasing erinacine A content by 62.21% and 146.70% at 20 days, respectively. Transcriptome and WGCNA of inducer-treated sample identified darkorange and magenta modules associated with erinacine A biosynthesis, with the eri gene cluster enriched in the darkorange module and eriG and eriF as hub genes. Forward genetic analysis via QTL mapping of the HeD127 dikaryon population revealed significant phenotypic variation in erinacine A content (0.341-13.085 mg/g) and identified two loci (erA-1 and erA-2) explaining 18.63% of phenotypic variation. Integrating these forward and reverse genetic analyses revealed that salicylic acid and ergosterol synergistically regulate core carbon metabolic pathways to augment acetyl-CoA supply for the mevalonate pathway, suppressed competitive metabolism, enhanced diterpene skeleton construction and structural modification. These results deepen our understanding of the genetic and molecular basis governing accumulation of erinacine A, and facilitate its application in neuroprotective pharmaceuticals.

Diterpenes

Lipid-mediated activation of BLT2 promotes membrane repair to prevent cell death.

Various pathogenic microorganisms produce toxins that create pores in cell membranes, causing cell damage and disrupting the host epithelial barrier. Recently, we reported that mice lacking the G protein-coupled receptor leukotriene B4 receptor 2 (BLT2), which is expressed in vascular endothelial and alveolar epithelial cells, are highly susceptible to pneumolysin (PLY), a pneumococci-generated toxin. Although we clarified the protective roles of BLT2 in vascular endothelial cells, those in alveolar epithelial cells have not been elucidated. Here, we report that lipid mediator 12-hydroxyheptadecatrienoic acid (12-HHT), which is produced by membrane-damaged epithelial cells, prevents cell death by promoting membrane repair through BLT2. BLT2 promoted the release of PLY-bound plasma membranes as extracellular vesicles in a sphingomyelinase-dependent manner. Additionally, BLT2 activated Rac1 and subsequent actin polymerization, leading to resistance to cell death. Furthermore, inhibition of 12-HHT production by aspirin and treatment with a BLT2 antagonist abolished the protective effect of BLT2. These findings provide a new therapeutic strategy for bacterial infection.

Receptors, Leukotriene B4

Advances in cereal protein applications for infant and Young child nutrition.

BACKGROUND: The increasing use of plant-derived proteins in infant and young child nutrition necessitates tailored amino acid profiles, high digestibility and strict safety controls. Cereal proteins, such as rice, oat, maize, millet, barley, and wheat, are widely used in complementary foods but face intrinsic limitations, notably lysine and tryptophan deficits, antinutritional factors that reduce bioavailability, gluten immunogenicity in wheat/barley, and inorganic arsenic risks in rice. SCOPE AND APPROACH: This review synthesizes recent advances in processing and formulation strategies, including enzymatic hydrolysis, fermentation, germination, extrusion, cereal-legume complementation, and micronutrient fortification. Their impacts on digestibility, techno-functionality, iron and zinc bioavailability, and protein quality, including Protein Digestibility-Corrected Amino Acid Score (PDCAAS) and Digestible Indispensable Amino Acid Score (DIAAS) are critically reviewed using data from in vitro assays, product development, and clinical trials. KEY FINDINGS AND CONCLUSIONS: Processing and blending approaches can substantially improve protein digestibility, amino acid balance and micronutrient availability, and hydrolyzed rice protein holds clinical promise for cow's milk protein allergy (CMPA). However, most evidence is preclinical, reporting of protein quality is inconsistent, and industrial translation is constrained by sensory, shelf-life, contaminant and cost issues. We recommend standardized DIAAS-based reporting, large-scale feeding trials, sensory /stability optimization, and targeted exploration of underutilized grains (e.g., oat, millet) with active allergen monitoring. Prioritizing amino acid-focused formulation coupled with strategies to enhance micronutrient bioavailability will accelerate safe adoption of cereal proteins in early-life nutrition.

Humans

Postoperative complications and outcomes after surgical treatment for tophaceous gout: A systematic review and meta-analysis.

BACKGROUND: Surgical treatment remains necessary for selected patients with tophaceous gout, particularly when mechanical limitation, nerve compression, ulceration, infection, deformity, or failure of conservative treatment is present. However, postoperative outcomes after surgery for tophaceous gout have not been comprehensively quantified. This systematic review and meta-analysis evaluated postoperative complication profiles and recurrence burden after surgical treatment for tophaceous gout. METHODS: A systematic search of PubMed, Embase, Web of Science, and the Cochrane Library was conducted from database inception to March 25, 2026. Original studies reporting postoperative outcomes after surgical treatment for tophaceous gout were included. Pooled event rates with 95% confidence intervals (CIs) were calculated using a random-effects single-arm meta-analytic approach. Primary outcomes were postoperative infection, delayed wound healing, and recurrence. Secondary outcomes were reoperation, amputation, and overall complications. Functional outcomes were summarized descriptively. RESULTS: 18 retrospective studies were included. The pooled postoperative infection rate was 11.3% (95% CI 8.0%-15.7%), delayed wound healing 9.9% (95% CI 5.1%-18.2%), and recurrence 8.5% (95% CI 4.7%-14.9%). Secondary pooled rates were 9.7% (95% CI 5.5%-16.7%) for reoperation, 3.7% (95% CI 2.0%-6.8%) for amputation, and 24.0% (95% CI 14.0%-38.1%) for overall complications. Significant subgroup differences were identified only for infection according to anatomic site and intervention type. Sensitivity analyses showed that pooled estimates were robust. The certainty of evidence was very low for all outcomes. CONCLUSIONS: Surgical treatment for tophaceous gout is associated with measurable postoperative risks, particularly infection and overall complications. These findings support careful perioperative counseling, structured postoperative surveillance, integrated long-term urate-lowering management, and more standardized reporting of perioperative risk factors and postoperative outcomes in future surgical studies of tophaceous gout.

Humans

Amino acid reprogramming and biofilm-specific tricarboxylate transporters in PET-degrading Piscinibacter sakaiensis.

Plastic-degrading bacteria predominantly colonize polymer surfaces as biofilms, yet it remains unclear whether the biofilm phenotype contributes to metabolism beyond retaining extracellular enzymes. Here, we combine population-level RNA-sequencing across three conditions-biofilm cells on polyethylene terephthalate (PET), planktonic cells incubated with PET, and planktonic cells on maltose-with single-cell Raman spectroscopy to characterize the PET response of Piscinibacter sakaiensis (formerly Ideonella sakaiensis). This integrated approach reveals two metabolically distinct response layers. A carbon-source-driven response shared by all PET-exposed cells is dominated by a broad amino acid reprogramming, led by upregulation of branched-chain amino acid transport genes, enhanced serine biosynthesis, and reduced chemotaxis. A biofilm-specific layer selectively induces tripartite tricarboxylate transporter genes from three distinct genomic loci. This transcriptional feature is accompanied by a single-cell phenotype consistent with a protein-rich and saturated membrane. These results suggest that biofilm formation is not limited to enzyme retention but is associated with selective activation of transport systems, consistent with a putative role in capturing PET-derived intermediates at the polymer interface. This two-layer model separates general metabolic adaptation to PET from biofilm-specific functions and provides a framework for understanding how surface-associated bacterial physiology contributes to plastic degradation.IMPORTANCEPolyethylene terephthalate (PET) degradation in natural and engineered environments is largely mediated by surface-attached microbial communities, yet the physiological role of biofilm state during plastic degradation remains poorly understood. Using the model PET degrader Piscinibacter sakaiensis, we show that biofilm-associated cells are not simply retained near the polymer surface but exhibit a distinct metabolic program characterized by selective induction of tripartite tricarboxylate transporters. In contrast, extensive amino acid reprogramming occurs in both biofilm and planktonic PET-exposed cells, indicating that it is driven by carbon source rather than surface attachment. These findings reveal that PET degradation involves two separable physiological layers: a general metabolic response to PET-derived carbon shared across cell phenotypes, and a biofilm-specific transport response potentially linked to substrate capture at the plastic interface. This work advances our understanding of how microbial physiology is organized during plastic biodegradation and identifies transport processes as previously unrecognized components of PET-degrading biofilms.

PET biodegradation

BLIS study: a feasibility randomised controlled trial assessing compliance, acceptability and colonisation with different dosing regimens of the probiotic supplement Streptococcus salivarius K12 (Bactoblis) in adults in England.

OBJECTIVES: Streptococcus salivarius K12 (SsK12) is a bacterium used as a probiotic with some evidence for preventing acute sore throat/tonsillitis, but the optimal dosing strategy is unclear. This study aimed to evaluate two dosing regimens of SsK12 to establish (a) the prevalence and duration of colonisation with SsK12 and (b) the acceptability and feasibility of these regimens. DESIGN: A randomised, non-blinded feasibility trial. SETTING: Primary care in the south of England. PARTICIPANTS: Adults with ≥2 episodes of sore throat within the 3 years before recruitment. INTERVENTIONS: Participants were randomised to take SsK12 lozenges once weekly or daily over 14 days. MAIN OUTCOME MEASURES: The primary outcome was the prevalence and duration of colonisation with SsK12. This was determined by real-time PCR conducted on self-taken whole-mouth swabs provided by participants at baseline and on days 2, 7, 14, 21 and 35. Secondary outcomes were the compliance and acceptability of the two SsK12 dosing regimens, based on questionnaire data. RESULTS: 53 participants were recruited (26 randomised to weekly and 27 to daily dosing) between 26 April and 5 December 2023. All swabs were returned by 65.4% (17/26) and 70.4% (19/27) of the weekly and daily groups respectively. Swabs at all timepoints from participants with PCR positives observed at baseline (two and four from the weekly and daily group, respectively) were excluded. Therefore, swabs from 23 participants in the weekly and 22 in the daily group did not have evidence of baseline colonisation and were included in the microbiology analysis. SsK12 colonisation was found in 59.1% (13/22, 95% CI 38.6% to 79.6%) of samples in both groups on day 2; in 13.6% (3/22, 95% CI 0.0% to 28.0%) and 85.7% (18/21, 95% CI 70.8% to 100.0%) of the weekly and daily groups, respectively, on day 7; in 19.1% (4/21, 95% CI 2.3% to 35.8%) and 59.1% (13/22, 95% CI 38.6% to 79.6%), respectively, on day 14; and in only one participant (weekly group) on days 21 and 35. The dosing regimen was reported as easy to follow by 85.0% (17/20, 95% CI 69.4% to 100.0%) of the weekly and 96.2% (25/26, 95% CI 88.8% to 100.0%) of the daily dosing groups. CONCLUSIONS: SsK12 colonisation was more prevalent with daily dosing; however, colonisation was not maintained when dosing stopped. Both dosing regimens were acceptable to participants. These findings support the use of daily dosing in a future trial to evaluate the efficacy of SsK12 in preventing recurrence of sore throat/tonsillitis. TRIAL REGISTRATION NUMBER: NCT04297878.

Humans

Simultaneously PYCR-1 and ALH-6 inhibition exacerbates 6-PPD quinone toxicity via disrupting proline and glutamate metabolisms and activating insulin signals in Caenorhabditis elegans.

Glutamate synthesized from the proline can serve as a precursor for key intermediate metabolites of citric acid cycle. Recently, we observed reduced glutamate content and expression of alh-6 controlling glutamate synthesis by 6-PPD quinone (6-PPDQ) in Caenorhabditis elegans. However, possible effect of 6-PPDQ on proline synthesis and the association with 6-PPDQ toxicity induction remain unclear. After 0.1-10 μg/L 6-PPDQ exposure, proline content was further reduced, and expression of pycr-1 governing proline biosynthesis was decreased. In 6-PPDQ exposed nematodes, RNA interference (RNAi) of pycr-1 decreased α-ketoglutarate content, enhanced mitochondrial dysfunction, reduced nicotinamide adenine dinucleotide (NADH) and reduced flavine adenine dinucleotide (FADH₂) contents, inhibited mitochondrial complex I/II activities, and decreased expressions of gas-1 and mev-1. Moreover, compared to single RNAi, double RNAi of pycr-1 and alh-6 exacerbated the 6-PPDQ toxicity in reducing α-ketoglutarate, NADH, and FADH₂ contents, and suppressing mitochondrial complex I/II activities and gas-1 and mev-1 expressions. Additionally, double RNAi of pycr-1 and alh-6 intensified toxicity of 6-PPDQ on longevity and caused upregulation of insulin ligand and receptor genes and downregulation of daf-16 and its targeted genes in 6-PPDQ exposed nematodes. Furthermore, after 6-PPDQ exposure, daf-16 RNAi suppressed pycr-1 and alh-6 expressions, suggesting formation of a regulatory feedback loop between pycr-1/alh-6 and daf-16. Our findings highlight involvement of disrupted proline and glutamate metabolisms in 6-PPDQ-induced mitochondrial dysfunction and reduced longevity.

Animals

Genomic determinants underlying biogenic amine detoxification phenotypes in food-associated lactic acid bacteria: Mechanism, evolutionary origin, and relevance to fermented food safety.

Biogenic amines (BAs) are toxic metabolites that accumulate in fermented foods and pose significant food safety concerns. Although several lactic acid bacteria (LAB) have previously been reported to exhibit strain-specific BA-degrading phenotypes, the genetic determinants underlying these activities have remained largely uncharacterized. Here, we analyzed 8251 LAB genomes to validate BA-degrading phenotypes. We predicted five BA-associated genes, including two direct biogenic amine-degrading genes (BADGs), mco and patA, and three polyamine-modifying genes (PMGs), speG, paiA, and bltD. Among BADGs, mco was broadly distributed across LAB and strongly enriched across food-associated niches. patA, organized within a conserved potD-glnB-potABC-patA cassette, is a putative, functionally distinct BADG in LAB, revealing a nitrogen-responsive polyamine uptake-catabolism module. Phylogenomics, phylogenetic reconciliation, and synteny analysis established that all five genes entered the LAB through episodic horizontal gene transfer followed by lineage-specific fixation. GC compositional bias and mobile genetic element association further corroborated the horizontal origin of the two BADGs. Structural analysis confirmed the conservation of catalytic core residues of BADGs across LAB, indicating strong purifying selection. Phenotype-to-genotype correlation with experimentally reported LAB suggested mco as a reliable genomic predictor of degrading phenotype. Integration of degradation and biosynthetic profiles predicted multiple LAB species capable of both synthesizing and degrading BA, along with 1823 genomes with degradation potential but lacking detectable BA biosynthesis genes. This study provides the first large-scale genome framework linking BA-degrading phenotypes with their genetic determinants in LAB and offers a rational basis for selecting BA-detoxifying strains for fermented food applications.

Biogenic Amines