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PubMed2026

Inactivation of Aspergillus flavus spores by dielectric barrier discharge cold plasma: Kinetics, physiological properties and proteomic analysis.

A. flavus, as a pathogen, poses a grave threat to both human and livestock health, significantly influencing agricultural production as well. This study aimed to investigate the inactivation effect and mechanism of dielectric barrier discharge cold plasma (DBD-CP) on A. flavus spores. The results exhibited that DBD-CP effectively inactivated A. flavus spores by the Weibull + Tail model. Furthermore, the physiological and proteomic analysis revealed that DBD-CP destructed cell wall and membrane integrity, causing cellular protein leakage and increasing membrane penetration of ROS generated from DBD-CP. Although intracellular ROS was excessively accumulated, the protein levels and activities of SOD and CAT were decreased, indicating that intracellular redox homeostasis was disrupted by DBD-CP. Subsequently, DBD-CP treatment induced cellular protein oxidation and changed protein structures, resulting in unstable protein structures. Meanwhile, protein synthesis and degradation in A. flavus spores were disturbed by inhibiting ribosome biogenesis, initiation process and NEDD8-mediated UPS, which did not compensate for the loss of protein caused by oxidative damage and leakage, leading to A. flavus spore inactivation. Besides, DBD-CP could attenuate A. flavus virulence by downregulating hydrolytic enzymes and CFEM-related proteins. This study provides novel insight into the inactivation mechanism of DBD-CP against A. flavus spores, which establishes a basis for the application of DBD-CP in controlling pathogenic fungi contamination in grains and crops, promoting the development of DBD-CP in food and agricultural decontamination.

Spores, Fungal↗

PubMed2026

Integrated electronic nose, GC-MS, and metagenomic analyses reveal volatile flavor and microbial community differences in heap-fermented grains of Jiangxiangxing Baijiu across different fermentation degrees.

The fermentation degree of heap-fermented grains in Jiangxiangxing Baijiu production is a critical factor influencing base Baijiu quality. However, conventional assessment methods largely rely on empirical experience and therefore suffer from limited objectivity and accuracy. In this study, integrated volatile profiling and metagenomic approaches were employed to investigate volatile characteristics and microbial functional potential differentiation in fermented grains with different fermentation degrees (under-fermented, normally fermented, and over-fermented). Significant differences in physicochemical properties were observed among fermentation degrees, particularly in acidity and reducing sugar content. Electronic nose analysis revealed distinct sensor response patterns among different fermentation degrees, indicating differences in overall volatile odor fingerprint patterns. A total of 81 volatile compounds were identified by HS-SPME-GC-MS, with aldehydes, ketones, and pyrazines showing pronounced variations among fermentation degrees, and acetaldehyde exhibiting strong discriminatory potential. LEfSe analysis identified 18 microbial taxa as potential biomarkers associated with different fermentation degrees, including Pichia kudriavzevii, Lentibacillus daiqui, and Acetobacter pasteurianus. Correlation analysis revealed significant positive associations between acetaldehyde levels and Acetobacter abundance. Furthermore, KEGG, CAZy, and eggNOG analyses revealed differentiated functional potentials among fermentation degrees, providing insights into the potential metabolic basis associated with flavor differentiation. Overall, these findings highlight that fermentation degree differentiation is closely associated with coordinated changes in physicochemical conditions, microbial communities, and functional potentials, providing ecological insights into flavor differentiation and theoretical support for objective fermentation degree evaluation and quality control of Jiangxiangxing Baijiu production.

Fermentation↗

PubMed2026

Insights into specific and nonspecific butyrate-producing pathways during the in vitro fecal fermentation of butyrylated starch.

Butyrylated starch is a special type-4 resistant starch with butyrate-carrying attribute. In this study, the unique butyrate-producing capability of butyrylated starch was deeply investigated by focusing on its specific and nonspecific butyrate-producing pathways, respectively, using specially designed substrates as controls. In vitro fermentation studies revealed that butyrylated and isobutyrylated starches generated high levels of butyrate and isobutyrate, respectively, highlighting the role of butyryl group metabolism in the specificity of butyrate production. Carboxylesterase assays have demonstrated that butyryl group metabolism is primarily facilitated by carbohydrate esterases expressed in the gut microbiota. Combined with 16S rRNA sequencing and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, it was found that butyrylated starch fermentation did not significantly enhance traditional butyrate synthesis pathways but modified the balance between the butyryl-CoA:acetyl-CoA transferase and butyrate kinase pathways by altering the gut microbiota composition, specifically by upregulating the relative abundance of indicator species such as Bacteroides, the Lachnospiraceae_NK4A136_group, and Parabacteroides. These insights offer theoretical guidance for designing butyrylated starch structures and regulating intestinal health.

Starch↗

PubMed2026

Depth-dependent microbial succession and interspecies hydrogen transfer drive pit mud maturation in Chinese strong-flavor baijiu fermentation.

Microbial communities in fermentation pit mud play a key role in determining the quality of Chinese strong-flavor baijiu (CSFB). However, the ecological processes underlying pit mud maturation across spatial and temporal scales remain unclear. In this study, amplicon sequencing and metagenomic analyses were employed to investigate the taxonomic succession, community assembly, and metabolic functions of bacterial and archaeal communities during the transition from fresh pit mud (FPM) to new pit mud (NPM) and old pit mud (OPM). A pronounced depth-dependent succession pattern was observed, with 4 cm representing a critical ecological boundary separating distinct community structures and maturation trajectories. During surface-layer maturation, community assembly shifted from stochastic to deterministic processes, accompanied by homogeneous selection and increasing network complexity. In contrast, stochastic processes remained dominant throughout deep-layer maturation. Metagenomic analyses revealed a functional transition from lactate and acetate production, primarily associated with Lactobacillus in FPM and NPM, to butyrate and caproate production associated with Clostridium and Caproiciproducens in OPM. This functional transition was accompanied by enhanced amino acid metabolism, which was associated with the enrichment of Proteiniphilum and Aminobacterium. Notably, methanogen-mediated interspecies hydrogen transfer (IHT) emerged as a key ecological feature during pit mud maturation. In OPM, IHT networks primarily involving Methanobacterium and Methanosarcina linked methanogenesis with reverse β-oxidation through diverse hydrogen-transfer pathways, reinforcing metabolic interactions underlying caproate production. These findings provide new insights into the ecological mechanisms underlying pit mud maturation and offer a theoretical basis for the directed cultivation of high-quality pit mud in CSFB production.

Hydrogen↗

PubMed2026

From commensal to pathobiont: The emergence of virulence-enhanced Escherichia coli in China's food-animal systems - insights with future implications.

A fundamental shift in Escherichia coli epidemiology is being driven by convergence of virulence determinants and antimicrobial resistance within linked human-animal-environment systems. In China, the rapid growth of food-animal production, extensive antimicrobial use, and complex food networks are accelerating the emergence and dissemination of virulence-enhanced E. coli pathobionts. This review synthesizes recent epidemiological, genomics, and outbreak data to characterize China's evolving landscape of food-animal-associated E. coli. We highlight a significant shift from classical pathotypes to hybrid lineages that simultaneously carry virulence factors and last-resort antibiotic resistance determinants, including mcr-1, tet(X4), and blaNDM. These traits disseminate rapidly via plasmid-mediated horizontal gene transfer, facilitating rapid adaptation and enabling cross-sectoral One Health transmission. National surveillance, foodborne outbreak investigations, and whole-genome sequencing data show that food-animal reservoirs are active evolutionary niches that drive pathogen diversity and fitness, rather than serving merely as contamination sources. Whole-genome sequencing also pinpoints high-risk clones (e.g., ST394) and plasmid-mediated co-selection of virulence and AMR. The emergence of hybrid pathotypes (e.g., STEC/ETEC) and AMR-virulence co-selection challenges traditional classification and limits the effectiveness of conventional surveillance approaches. The 2017 colistin ban reduced mcr-1, yet ongoing resistance and emerging tet(X4) demand integrated surveillance. Collectively, these findings call for reconceptualizing E. coli as a dynamic genomic entity embedded within a unified ecological network. Addressing this threat requires an integrated One Health strategy including genomic surveillance, agricultural antimicrobial stewardship, and coordinated food-environment-clinical monitoring to prevent high-risk clone emergence and global spread.

Animals↗

PubMed2026

Forensic taphonomy in fluvial water: A systematic review.

Human remains are frequently recovered from fluvial (lotic) water environments. Rivers, streams, canals and other flowing water bodies pose distinct challenges in forensic practice, particularly due to their current. Compared to other aquatic contexts, fluviatile taphonomy is underrepresented in the forensic literature and the last comprehensive summary was written over a decade ago. Therefore, a systematic review was performed to collect and summarise the current knowledge in forensics about fluvial taphonomy, including decomposition of remains, transport characteristics, search, postmortem submersion interval (PMSI) estimation, taphonomic alterations, and differences to other water bodies. 92 reports met the inclusion criteria for this review, most of them showed a moderate risk of bias. Their main findings were summarised and two major challenges identified. First, predictions about fluvial transport of human bodies pose a tremendous issue in forensic practice, leading to later detection and lower recovery rate of remains, complicating various subsequent analyses. Second, PMSI estimations are difficult particularly due to variable environmental conditions in fluviatile systems. Recommendations for future research in the area of fluvial forensic taphonomy include that case-related data such as the detailed decomposition state and river characteristics need to be made available. More standardised research protocols are required for a facilitated comparison between studies, environments and regions. This review provides forensic practitioners with a comprehensive, updated resource for the investigation of fluvial remains. It also guides future research towards a more efficient practice to build the basis for a broader, more robust and comprehensive synthesis, subsequently supporting analyses in forensic casework.

Humans↗

PubMed2026

Protein persulfidation emerges as a conserved component of the redox response to DNA damage.

Genotoxic stress is frequently accompanied by alterations in cellular redox homeostasis; however, the mechanisms linking redox regulation to the DNA damage response (DDR) remain incompletely understood. Here, we investigated the early redox response to DNA damage induced by methyl methanesulfonate (MMS) in Saccharomyces cerevisiae, focusing on cysteine oxidative post-translational modifications (PTM). We show that activation of the DNA damage response is accompanied by rapid redox changes that occur in the absence of a generalized oxidative stress response. MMS exposure promotes selective remodeling of cysteine oxidative modifications, characterized by decreased free thiols, robust induction of protein persulfidation, and comparatively modest changes in sulfenylation. These alterations are accompanied by increased intracellular hydrogen sulfide levels, supporting the involvement of reactive sulfur species in the cellular response to DNA damage. Proteome-wide analyses revealed that cysteine oxidative modifications preferentially target proteins involved in central metabolism, nucleotide biosynthesis, and genome maintenance. Consistent with these observations, MMS-induced genotoxic stress promotes metabolic adaptation characterized by increased mitochondrial respiration, elevated ATP production, and mitochondrial morphological remodeling, linking bioenergetic adaptation to redox regulation. Importantly, perturbation of intracellular redox balance using N-acetylcysteine compromises survival under DNA-damaging conditions, supporting a functional role for redox signaling during the DDR. Finally, MMS treatment also induces protein persulfidation in mammalian cells. Moreover, exposure to etoposide, a mechanistically distinct genotoxic agent that induces DNA double-strand breaks through topoisomerase II inhibition, showed a similar trend, suggesting that protein persulfidation may not be restricted to alkylation-induced DNA damage. Together our findings identify protein persulfidation as a prominent component of the redox response to DNA damage and provide new insight into the functional interplay between mitochondrial metabolism, cysteine-based redox regulation, and genome maintenance.

Oxidation-Reduction↗

PubMed2026

Mitochondrial DNA diversity in Ecuadorian populations: Recurrence of variant 16136 within haplogroup B2.

The identification of lineage-defining variants, frequently found in the coding region of mitochondrial DNA (mtDNA), is essential for refining haplogroup classification. Most mtDNA studies in South American populations have focused on the control region (CR), which has provided important insights into population structure and maternal lineage origins, although information needed for more robust phylogenetic resolution has been neglected. This study investigates the maternal genetic structure of Ecuadorian populations by combining CR and whole mitogenome analyses. Sequences from the mtDNA CR were obtained from 461 individuals (253 Mestizos and 208 Native Americans), while complete mitogenomes were sequenced for 127 individuals to improve phylogenetic resolution by identifying lineage-defining variants present in coding region. Most mtDNA haplogroups in the two population groups analyzed were of Native American origin (A2, B2, B4, C1, D1, D4), with significant differences in the distribution of specific lineages between them. Among Mestizos, African haplogroups (all within the L branches) and Eurasian haplogroups (H, K, R, U) were detected at low frequencies, whereas no African lineages were observed among Native Americans. The results obtained highlighted a heterogeneity within Ecuadorian populations that must be considered when developing mtDNA haplotype databases for forensic purposes. Whole mitogenome sequences enabled the identification of variants that refined haplogroup classifications, provided a more accurate reconstruction of the maternal genetic diversity, and improve the discrimination between Native American and Asian maternal lineages within haplogroup B4b.

Humans↗

PubMed2026

Optimizing focal vibration therapy for balance and gait: A systematic review.

OBJECTIVE: This systematic review evaluated the efficacy of focal (localized) vibration therapy (FVT) applied to muscles/tendons on balance, gait, and mobility, with a specific focus on defining optimal vibration protocols (frequency, amplitude, dosing) and muscle-targeting strategies to maximize sensorimotor recovery. METHODS: A systematic review was conducted across six databases (CINHAL, Embase, Medline, Web of Science, Scopus, CENTRAL) from January 2000 to May 2025. Studies were included if they involved human participants, applied FVT therapeutically, and reported balance, gait, or mobility outcomes. Data extraction included study characteristics, intervention protocols, and outcomes. Methodological quality was assessed using the PEDro scale. RESULTS: Sixty-two studies (n = 2090 participants) were included. Methodological quality assessment (PEDro scale) indicated 44% of studies met high-quality standards. Biomechanical analysis identified the quadriceps, gastrocnemius/soleus, and plantar muscles as the most effective vibration sites, given their critical roles in gait propulsion and postural stability. The synthesis of protocol data indicated a promising therapeutic window characterized by a vibration frequency of 80-120 Hz (primarily fixed sinusoidal waveforms at a single frequency) and an amplitude of 0.2-0.5 mm (reported only in 12 studies; amplitude was not reported in 23 studies), applied bilaterally for a minimum of 3 sessions per week over 4-12 weeks, which could lead to improved balance and gait performance with benefits sustained for up to 5 months. CONCLUSION: FVT shows potential to improve gait and balance, particularly when targeting lower-extremity muscles with optimized vibration parameters. To advance the field, future research must prioritize the development of standardized protocols and investigate neurophysiological mechanisms to refine FVT as a precision bioengineering solution for mobility deficits.

Humans↗

PubMed2026

The effect of combining visuo-vestibular exercises with manual therapy and exercise on sensorimotor function in chronic neck pain: A randomized controlled trial.

OBJECTIVE: To investigate whether adding visuo-vestibular exercises to standard manual therapy and exercise produces superior improvements in sensorimotor function, pain, balance, and functional disability in adults with chronic neck pain. METHODS: This prospective, randomized controlled trial enrolled 58 adults with chronic neck pain (≥3 months) allocated to a manual therapy and exercise group (MtE; n = 29) or MtE plus visuo-vestibular exercises (MtE-VVE; n = 29). Both groups completed 12 supervised sessions over six weeks with a daily home exercise programme. Outcomes were assessed at baseline, 6 weeks, and 12 weeks, and included pain intensity (Visual Analog Scale [VAS]), upper extremity reaction time, computerized posturography, the Neck Disability Index (NDI), and cervical muscle endurance. RESULTS: Fifty-four participants (27 per group) completed the study. Both groups improved significantly across all outcomes (p < 0.001). At 12-week follow-up, the MtE-VVE group demonstrated superior outcomes: activity-related pain was reduced by an additional 2.00 cm (95% CI: 0.75-3.25; p = 0.005), bilateral reaction time improved by 1.70 s (p = 0.001), eyes-open mediolateral sway decreased by 0.50 mm (p < 0.001), NDI score was 6.30 points lower (95% CI: 3.42-9.18; p < 0.001), and cervical flexion and extension endurance improved by 12.00 s and 27.70 s, respectively (p ≤ 0.020). CONCLUSION: Adding visuo-vestibular exercises to standard manual therapy and exercise produces clinically meaningful and sustained improvements in activity-related pain, sensorimotor function, postural control, and functional disability in adults with chronic neck pain, and may be recommended as an effective adjunctive intervention.

Humans↗

PubMed2026

An oxidative stress - and immunotherapy-related six-gene signature defines immune subtypes and predicts prognosis and immunotherapy response in hepatocellular carcinoma.

BACKGROUND: Oxidative stress and the tumor immune microenvironment jointly shape hepatocellular carcinoma (HCC) progression and response to immunotherapy, yet integrated biomarkers linking these processes are lacking. METHODS: Transcriptomic and clinical data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets were used to identify oxidative stress- and immunotherapyrelated differentially expressed genes (OSIRDEGs). Functional enrichment, weighted gene co-expression network analysis (WGCNA) and LASSO-Cox regression were used to construct a prognostic signature. Consensus clustering, TIDE, CIBERSORT and ssGSEA characterized immune phenotypes. Somatic mutation, copy-number and drug-response data were integrated to assess genomic alterations and drug sensitivity. Expression of model genes was validated by qRT-PCR and western blotting in HCC cell lines. RESULTS: We identified 24 OSIRDEGs enriched in cell-cycle and mitotic pathways. WGCNA intersection yielded 18 module genes, from which a six-gene signature (BUB1B, CDKN2A, CENPE, HMMR, PTTG1, SPP1) was derived. The signature robustly stratified patients into high- and low-risk groups with significantly different progression-free and disease-free survival in both TCGA-LIHC and GSE14520. Based on signature expression, two molecular subtypes were defined, exhibiting distinct survival, immune landscapes and predicted immunotherapy responsiveness. Model genes harbored recurrent alterations and showed significant correlations with anticancer agents. All six genes were upregulated at mRNA and protein levels in metastatic HCC cell lines versus normal hepatocytes. CONCLUSIONS: We systematically explored the landscape of OSIRDEGs in HCC, and proposed a validated six-gene signature that refines prognostic stratification, delineates immunerelevant HCC subtypes and highlights candidate biomarkers for therapeutic selection and mechanistic investigation.

Humans↗

PubMed2026

Linked-color imaging with computer-aided detection and the proximal adenoma miss rate: a randomized tandem trial.

BACKGROUND AND AIMS: Linked-color imaging (LCI) aids the detection and characterization of lesions. Computer-aided detection (CADe) systems have been introduced to improve lesion detection during colonoscopy. Although several studies have been reported regarding LCI, few have investigated the combination of LCI and CADe. This study aimed to evaluate the efficacy of LCI with CADe colonoscopy compared to conventional white-light colonoscopy. METHODS: A single-center, randomized tandem trial was conducted. Participants referred for first-time colonoscopy after fecal immunochemical test (FIT)-positive, asymptomatic screening, or surveillance colonoscopy were randomized (1:1) to undergo CADe-assisted colonoscopy of LCI or white-light imaging (WLI) in the right side of the colon. The primary outcome was adenoma miss rate (AMR) in the right side of the colon. Secondary outcomes included polyp miss rate (PMR), diminutive adenoma miss rate (dAMR), sessile serrated lesion miss rate (SSLMR), advanced adenoma miss rate, advanced neoplasia miss rate, flat-type lesion miss rate (FMR), and the differences in miss rates based on expertise. RESULTS: Among 232 randomized participants, 209 were analyzed (LCI/CADe: 102; WLI: 107). AMR (WLI: 39% vs LCI/CADe: 20%; P = .001), PMR (42% vs 18%; P < .001), and dAMR (42% vs 21%; P = .003) were significantly lower in the LCI/CADe arm, particularly among experts. SSLMR (46% vs 0%), advanced AMR (30% vs 0%), advanced neoplasia miss rate (25% vs 0%), and FMR (27% vs 5.6%) were lower in LCI/CADe, although without statistical significance. CONCLUSIONS: Compared to conventional colonoscopy, LCI with CADe colonoscopy resulted in a statistically significant decrease, especially in AMR. (UMIN 000050685).

Humans↗

PubMed2026

Evaluating the pathogenic significance of unique chromosomal variants in craniosynostosis using patient-derived induced pluripotent stem cells and mouse modelling.

PURPOSE: Unravelling causal links between unique structural/copy-number variants (SV/CNV) and associated phenotypes is essential for correct genetic counselling. We investigated two families in which patients with craniosynostosis had SV/CNV potentially dysregulating a fibroblast growth factor (FGF)-encoding gene; a 730 kb dup(4)(q21.21) including FGF5; and a complex 568 kb interspersed 13q12.11 duplication, located 841 kb from FGF9. METHODS: We combined bioinformatic predictions of altered topologically-associating domain (TAD) structure, with experimental analysis (RNA- and ATAC- [assay for transposase-accessible chromatin] sequencing) of patient induced pluripotent stem cell lines (iPSCs) differentiated to neural crest (NCC) and osteoprogenitor (OPC) identities. For the dup(4)(q21.21) we generated a mouse bearing an equivalent rearrangement using CRISPR-Cas9 targeting. RESULTS: TAD analysis suggested potential dysregulation of the FGF5/FGF9 gene by bringing it into a novel genomic milieu. The RNA- and ATAC-seq assays demonstrated FGF5/FGF9 upregulation (2.7-18x) and local opening of chromatin, in 3/4 cell lines. For the dup(4)(q21.21), a causal role was supported by the mouse model, whereas interpretation of the 13q12.11 SV is confounded by a co-existing FOXP2 pathogenic variant. CONCLUSION: Patient iPSC-differentiated NCC and OPC lines, combined with TAD-based modelling to generate testable functional hypotheses, provide valuable functional evidence when evaluating causation of unique SV/CNV in craniosynostosis.

copy-number variant↗

PubMed2026

Effect of urinary catheter securement band on meatal pressure injury in male intensive care patients: A randomized controlled trial.

OBJECTIVES: To investigate the effectiveness of a urinary catheter securement band in preventing meatal pressure injury (meatal-PI) in male ICU patients, and to identify associated risk factors and the timing of injury development. METHODS: A total of 248 adult male ICU patients were randomly allocated to an intervention group (n = 124) or a control group (n = 124) between December 2024 and April 2025. The intervention group received a catheter securement band in addition to standard care, while the control group received standard care alone. Meatal-PI was evaluated daily using a structured monitoring form and a validated staging system. RESULTS: The incidence of meatal-PI was significantly lower in the intervention group (6.5%) compared with the control group (16.1%) (p = 0.016). Multivariate analysis identified catheter securement, use of silicone catheters, higher Braden Scale scores, and shorter ICU length of stay as independent protective factors, while advanced age was associated with increased risk. Additional factors significantly associated with meatal-PI included comorbidities, higher device burden, latex catheter use, dry skin, lower Glasgow Coma Scale and Braden scores, sedation, and perineal oedema (p < 0.001). CONCLUSIONS: The use of a catheter securement band significantly reduces the incidence of meatal-PI in male ICU patients. Incorporating catheter securement devices into routine nursing care, prioritising silicone catheter use, and performing regular meatal assessments may enhance patient safety by reducing the risk of device-related pressure injuries. Further research comparing different catheter securement methods across diverse patient populations is warranted. IMPLICATIONS FOR CLINICAL PRACTICE: The use of catheter securement bands may reduce the incidence of meatal-PI in male ICU patients. Incorporating standardized catheter stabilization strategies into routine intensive care nursing practice may enhance patient safety and support pressure injury prevention efforts.

Humans↗

PubMed2026

Diverse structures of mcr-10-bearing plasmids and high colistin resistance in Enterobacter cloacae complex clinical isolates from South Korea.

BACKGROUND: The emergence of mcr-mediated colistin resistance in Enterobacter cloacae complex (ECC) poses a significant threat to antimicrobial therapy. Among mcr variants, mcr-10 has been identified in various environments, but its genetic diversity, structural context, and functional role in colistin resistance remain unclear. METHODS: We investigated 183 ECC isolates and identified 60 colistin-resistant strains through minimum inhibitory concentration (MIC) testing. The presence of mcr-10 was screened using reference genomes from NCBI, and whole plasmid sequencing was conducted on mcr-10-positive isolates. The genetic environment of mcr-10 was analyzed via synteny and structural annotation. RESULTS: Whole-plasmid sequencing of eight mcr-10-positive ECC isolates identified three replicon types among the mcr-10-harboring plasmids: IncFIB (n=3), IncFII (n=3), and IncFII/IncFIB (n=2). Although all plasmids shared the xerC-mcr-10 cassette, they lacked a conserved backbone and showed diverse genetic contexts with variable insertion sequences near mcr-10, indicating marked structural heterogeneity. No additional antimicrobial resistance genes were detected on these plasmids. When introduced into E. coli DH5α, the plasmids increased colistin MICs only modestly, whereas representative plasmids transferred into colistin-susceptible E. roggenkampii and E. kobei conferred high-level resistance comparable to that of the parental mcr-10-positive isolates. Consistently, qRT-PCR showed higher mcr-10 expression in ECC transformants than in E. coli under colistin exposure, supporting a hostdependent effect on mcr-10-mediated colistin resistance. CONCLUSION: These findings highlight the diversity of mcr-10-carrying plasmids and suggest that mcr-10-mediated colistin resistance is shaped by the host genetic background. Further studies are needed to clarify the mechanisms underlying mcr-10 expression.

Colistin↗

PubMed2026

Comparative analysis of lipopolysaccharide lipid A structure and its biosynthetic genes in the plant-associated bacteria Brucella cytisi and Brucella lupini.

The genus Brucella comprises important human and animal pathogens, as well as numerous environmental and symbiotic species. Lipopolysaccharide (LPS), a major component of the outer membrane of Gram-negative bacteria, plays a crucial role in bacterial physiology and host interactions. In this study, the structures of lipid A, the hydrophobic anchor of lipopolysaccharide, isolated from two plant-associated strains, Brucella cytisi ESC1ᵀ and Brucella lupini LUP21ᵀ, were presented. Lipid A preparations were structurally characterized using chemical methods, MALDI-TOF mass spectrometry, and nuclear magnetic resonance spectroscopy. The obtained results indicated that both lipid A molecules have almost identical structures. Their sugar backbones consist exclusively of 2,3-diamino-2,3-dideoxy-d-glucose (d-GlcpN3N). Phosphate residues were connected to distal and proximal GlcpN3N in approximately half of the lipid A molecules. Fatty acid analysis revealed the presence of C14:0 (3-OH), C16:0 (3-OH), and traces of C18:0 (3-OH). All of these were primary fatty substituents of the sugar backbone and were amide-linked residues. Lactobacillic acid C19:0cyc and 27-hydroxyoctacosanoic acid (C28:0 (27-OH)) were found as ester-linked secondary acyl residues. In turn, C28:0 (27-OH) was partly esterified by a 3-hydroxybutyroyl residue. Two unsubstituted 3-hydroxyfatty acids were linked exclusively to the proximal d-GlcpN3N residue. It was pointed out that sequences of putative genes encoding enzymes required for lipid A biosynthesis and genes encoding specific enzymes involved in structural modifications of lipid A occurring in the genomes of both bacterial species are almost identical. The high sequence similarity of these proteins reflects the observed similarities in the lipid A structures in both investigated Brucella species.

Brucella↗

PubMed2026

Emergence of an optrA-positive Enterococcus faecalis ST699 lineage in animal-derived foods in Beijing, China.

Enterococci from animal-derived foods are key reservoirs for antimicrobial resistance (AMR) in the food chain. However, comparative genomic studies investigating the distribution of the oxazolidinone resistance gene optrA among food- and human-derived Enterococci remain limited. This study assessed linezolid-resistant Enterococci from retail meat and healthy humans in Beijing, China (2023-2024). Among 87 isolates, E. faecalis and E. faecium predominated. Food-derived isolates showed broader resistance profiles than human isolates. Fourteen optrA-positive strains were identified, accounting for 92.9% of food isolates. optrA frequently co-localized with erm(A), ant(9)-Ia, and fexA on Tn554-family transposons, suggesting a potentially transferable multidrug resistance module. Notably, an optrA-positive E. faecalis ST699 clone was identified for the first time in Chinese retail meat. This clone formed a distinct lineage and carried a complete Tn554-optrA island. A representative ST699 isolate exhibited enhanced fitness and virulence potential in the Galleria mellonella model. These findings highlight animal-derived foods as important reservoirs of linezolid-resistant Enterococci and provide genomic evidence consistent with their role as potential sources of optrA-mediated resistance. The emergence of a multidrug-resistant E. faecalis ST699 clone with enhanced fitness characteristics underscores the need for continued surveillance of foodborne antimicrobial resistance within the One Health framework.

Enterococcus faecalis↗

PubMed2026

From buffalo to human: Klebsiella pneumoniae in high-somatic cell count milk as an overlooked link in the one health chain.

High somatic cell count (SCC) is a critical indicator of udder health and milk quality in buffalo milk production. However, in many low-income regions, SCC monitoring is often underemphasized, allowing a proportion of high-SCC buffalo milk to enter the food chain and potentially compromising food safety and public health. Klebsiella pneumoniae (K. pneumoniae) is a common zoonotic pathogen found in high-SCC milk, yet systematic investigations into the prevalence and characteristics in high-SCC buffalo milk remain limited. In this study, 23 K. pneumoniae strains were screened out from 460 bacterial isolates obtained from high-SCC buffalo milk samples from Guangxi, China, with an isolation rate of 5.0%. These isolates were comprehensively characterized using whole-genome sequencing and comparative genomic analyses. The results revealed that 78.26% (18/23) of the isolates shared high genomic similarity with the human reference strain ATCC 13883, and the ST37 clone exhibited a pronounced potential of cross-species transmission. All isolates harbored core adhesion factors and intrinsic resistance genes. Notably, several strains displayed high-risk features: strain 419 carried the K1 capsular serotype, strain 326 possessed a complete yersiniabactin synthesis gene cluster, and strain 320 exhibited a multidrug-resistant phenotype. Phenotypic assays further demonstrated a positive correlation between biofilm formation capacity and virulence in Galleria mellonella. Metabolic pathway enrichment analyses suggested that K. pneumoniae has undergone substantial adaptation to the nutrient-rich buffalo milk environment. Collectively, these findings confirm that raw high-SCC buffalo milk serves as a significant reservoir for high-risk zoonotic K. pneumoniae. While industrial thermal processing effectively eliminates viable pathogens, the resilient antimicrobial resistance determinants within these isolates pose a persistent risk of horizontal gene dissemination along the food chain, providing critical evidence for enhancing pre-processing milk quality regulations within a One Health framework.

Animals↗