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PubMed2025

Application of Perioperative Real-Time Fluorescence Imaging to Achieve High-Quality Debridement: A Randomized Control Trial.

OBJECTIVE: To investigate the effectiveness of real-time fluorescence imaging (RTFI)-assisted debridement in managing chronic wounds compared with standard surgical debridement. APPROACH: This study was a patient-blinded, randomized clinical trial conducted from February 17, 2021, to July 30, 2021, on patients with chronic wounds. Patients were randomized to an RTFI group (M group) or conventional group (C group). The primary outcomes were as follows: percentage of residual bacterial area (preoperative and postoperative), number of debridements, high-quality debridement ratio, operation duration, and wound healing duration. RESULTS: A total of 100 patients were enrolled in both groups. No significant difference in the percentage of preoperative residual bacterial area or high-quality debridement ratio was seen. The M group underwent debridement an average of 2.6 times and had a significantly longer duration of operation (33.5 ± 12.7 min) than the C group (29.9 ± 10.4 min; p = 0.031). The postoperative residual bacterial area was significantly lower in the M than in the C group (6.83% ± 1.39% vs. 30.0% ± 12.37%, respectively; p < 0.001). The M group required significantly fewer wound healing days (49.2 ± 25.3 vs. 63.0 ± 27.9, p < 0.001). Secondary outcomes also demonstrated statistically significant differences in total hospitalized days (17.5 ± 9.3 vs. 21.5 ± 12.5, p < 0.01), days of antibiotic use (15.5 ± 8.7 vs. 18.7 ± 6.7, p < 0.01), and reinfection rates (4 of 100 vs. 22 of 100, p < 0.001). INNOVATION: RTFI can detect signals from normal skin components and bacterial metabolites. Therefore, interpretation of RTFI results should be correlated with the clinical condition. RTFI is associated with high-quality debridement. This technique can also be applied in targeted biopsy and in training young staff to mature debridement procedures. CONCLUSION: RTFI in debridement is associated with favorable clinical outcomes and may have a positive influence on chronic wound healing.

Humans↗

PubMed2026

Vancomycin Effectiveness in Reducing Surgical Site Infection in Posterior Spinal Fusion Surgery: A Retrospective Data Analysis of the STRIVE Trial.

STUDY DESIGN: Retrospective analysis of prospectively collected data. OBJECTIVE: To re-evaluate vancomycin as a preventive measure for surgical site infection (SSI). SUMMARY OF BACKGROUND DATA: Intrawound vancomycin powder is used to prevent SSIs in spinal surgery. Prior studies, often limited to single institutions or small samples, have shown mixed efficacy and potential increases in non- S. aureus and Gram-negative infections. We hypothesized that SSIs rates would be similar with and without intrawound vancomycin in posterior spinal fusion (PSF) surgery. METHODS: Prospectively collected data from the 3595 patients in the STaphylococcus aureus suRgical Inpatient Vaccine Efficacy (STRIVE) trial were stratified by intrawound antibiotic usage. Multivariate logistic regression assessed the effect of vancomycin use on SSI, adjusting for patient demographics and SSI-associated risk factors. Secondary outcomes included critical care stay, reoperation, sepsis, and hospital readmission. RESULTS: Of 3311 patients who underwent surgery, 847 (26%) received only intrawound vancomycin and 1534 (46%) received no intrawound antibiotics. Sixty (8%) patients developed postoperative SSI, of whom 20 (33%) had received intrawound vancomycin. Receiving intrawound vancomycin was not associated with SSI incidence versus no intrawound antibiotics [odds ratio (OR): 0.77; 95% CI: 0.42-1.42], critical care stay (OR: 0.94; 95% CI: 0.78-1.12), or sepsis (OR: 2.04; 95% CI: 0.62-6.73). However, intrawound vancomycin was associated with increased odds of hospital readmission (OR: 1.82; 95% CI: 1.28-2.6; P < 0.001) and reoperation (OR: 1.75; 95% CI: 1.18-2.6; P = 0.005). Factors significantly associated with intrawound vancomycin use included intraoperative antibiotic readministration (OR: 2.97; 95% CI: 1.36-6.5; P =0.006) and hospital location, lower odds in Europe (OR: 0.13; 95% CI: 0.06-0.29; P < 0.001) or Asia (OR: 0.02; 95% CI: 0-0.08; P < 0.001) versus North America. CONCLUSIONS: Intraoperative vancomycin use was not associated with reduced SSI incidence compared with no intrawound antibiotics after PSF surgery. LEVEL OF EVIDENCE: Level II.

Humans↗

PubMed2026

Randomized controlled trial comparing 7-day fexuprazan-based and 14-day rabeprazole-based triple therapies for Helicobacter pylori eradication.

BACKGROUND: Fexuprazan is a newly developed potassium-competitive acid blocker used for the treatment of acid-related gastrointestinal diseases; however, clinical data regarding its efficacy in Helicobacter pylori eradication are lacking. This study evaluated the efficacy and safety of a 7-day fexuprazan-based triple therapy regimen compared with a 14-day rabeprazole-based triple therapy regimen for H. pylori infection in Korean patients. METHODS: A randomized controlled single-center study was conducted to compare the eradication rates between 7-day fexuprazan (40 mg)-based triple therapy (with 1 g amoxicillin and clarithromycin 500 mg administered twice daily) and 14-day rabeprazole (20 mg)-based triple therapy for H. pylori eradication. The primary endpoint was the success rate of H. pylori eradication, determined using the 13C-urea breath test. Safety outcomes were also evaluated. RESULTS: A total of 79 patients were randomly assigned to the fexuprazan and rabeprazole groups. In the full analysis set, eradication rates were 80.00% (32/40) in the fexuprazan group and 82.05% (32/39) in the rabeprazole group. In the per-protocol set, eradication rates were 83.78% (31/37) and 88.89% (32/36), respectively (P = 1.000 and P =.737). The overall incidence of treatment-emergent adverse events was 70.00% (28/40) in the fexuprazan group and 66.67% (26/39) in the rabeprazole group, with no significant difference between groups (P =.812); both regimens were well tolerated. Among patients with clarithromycin-susceptible strains in full analysis set, eradication rates were 93.10% (27/29) in the fexuprazan group and 87.09% (27/31) in the rabeprazole group (P =.672). In the per-protocol set, eradication rates for susceptible strains were 96.42% (27/28) in the fexuprazan group and 93.10% (27/29) in the rabeprazole group (P = 1.000). CONCLUSION: Seven-day fexuprazan-based triple therapy demonstrated eradication efficacy comparable with that of 14-day rabeprazole-based therapy in treatment-naïve Korean patients with H. pylori infection. The fexuprazan-based regimen showed a similar safety profile and comparable incidence of adverse events with that of the rabeprazole-based regimen.

Humans↗

PubMed2026

Fracture-related infection following open forefoot fractures caused by dropped objects.

INTRODUCTION: This study evaluated the rate of fracture-related infection (FRI) of open forefoot fractures caused by dropped objects, and examined associations of treatment characteristics, including intravenous and oral antibiotics and operative debridement, with FRI. METHODS: Patients aged 18-80 years who sustained an open metatarsal or phalanx fracture caused by a dropped object between January 2021 and June 2024 were retrospectively identified from two Level 1 trauma centers. The primary outcome was FRI, determined based on the FRI consensus criteria. FRI rates were compared between those who underwent irrigation and debridement (I&D) at bedside versus in the operating room, and between those who received oral versus intravenous (IV) antibiotics. Patient characteristics were also analyzed to determine host factors associated with FRI. RESULTS: A total of 86 patients (median age 41 years [IQR: 29-56], 58% male) were included. Eighty-five patients (99%) received antibiotics, 31 (36%) of whom received intravenous antibiotics. Sixty-six patients (77%) received an I&D at presentation, 57 (66%) at bedside and 9 (10%) in the operating room. Thirteen patients (15%, 95% CI: 8.3%-24%) developed FRI. No significant difference in FRI rate was found between patients who underwent I&D at bedside versus in the operating room (12% versus 11%, p > 0.99). Among patients who did not undergo I&D in the operating room, no significant difference in FRI rate was found between patients who received oral versus IV antibiotics (17% versus 13%, p = 0.74). Insulin-dependent diabetes was associated with an increased risk of FRI (60% versus 12%, p = 0.02). CONCLUSIONS: In this cohort, one in seven patients developed FRI. No statistically significant differences in FRI rates were observed by I&D setting (bedside versus operative) or antibiotic route (oral versus IV), including in a subgroup analysis excluding patients treated with operating room I&D. These findings are limited by sample size and potential treatment selection bias and should not be interpreted as evidence of equivalence. Management should be individualized based on clinical judgement, resource availability, and patient factors. These findings can help guide the management protocols for "dropped objects" open forefoot fractures presenting to urgent care and the emergency department. LEVEL OF EVIDENCE: Therapeutic Level III.

Humans↗

PubMed2026

Pre-clinical evaluation of the anticaries effect of an experimental Malva sylvestris extract mouthwash using a cariogenic model in situ.

OBJECTIVE: The aim of this study was to evaluate the antimicrobial and anticariogenic potential of Malva sylvestris extract on enamel and dentin in situ. METHODS: A double-blind crossover in situ study was conducted with 12 participants wearing palatal appliances containing two bovine enamel and two dentin specimens per 3 phases, a total of 72 enamel and dentin specimens. Biofilm formation and daily sucrose exposure were allowed. Treatments were applied twice daily in three phases: Malva sylvestris (2.5%, MS); fluoride (225 ppm, F); and placebo (P). After seven days, biofilm was collected from the bovine specimens for analysis of Lactobacillus spp. and mutans streptococci by Colony Forming Unit counts (CFU log₁₀/mL). Dental demineralization of the bovine specimens was assessed by transverse microradiography (TMR). RESULTS: MS did not reduce Lactobacillus spp. counts (CFU log₁₀/mL: enamel 6.63±0.81; dentin 6.68±0.92) compared to P (6.63±0.70; 6.62±0.51). F also did not differ (6.29±0.75; 6.32±0.41; ANOVA/Tukey, p>0.38). Mutans streptococci data were inconclusive. In enamel, both MS (2320.8±768.2 %vol·µm; 101.6±27.0 µm) and F (1777.3±733.3 %vol·µm; 95.8±23.5 µm) significantly reduced integrated mineral loss and lesion depth compared to P (3517.2±1119.9 %vol·µm; 138.6±19.5 µm; ANOVA/Tukey, p≤0.0003). In dentin, MS significantly reduced integrated mineral loss (322.5 [250-580] %vol·µm) and lesion depth (30.1 [15-42.2] µm) compared to P (880 [580-1705]; 58.3 [32.2-88.6] µm; Kruskal-Wallis/Dunn, p≤0.001), while F (587.5 [305-720]; 25.2 [16.5-38.8] µm) did not differ significantly (p>0.05). CONCLUSIONS: Malva sylvestris extract had no antimicrobial effect on Lactobacillus spp. counts, but significantly reduced enamel and dentin demineralization, showing anticaries effect comparable to fluoride. CLINICAL RELEVANCE: Malva sylvestris has demonstrated promising biological activity. This study investigates the antimicrobial efficacy of Malva sylvestris against cariogenic microorganisms in situ. Our findings provide relevant evidence that M. sylvestris exert significant anticaries effects using an in situ model.

Biofilms↗

PubMed2026

S-layer-phage interaction in Clostridioides difficile.

Successful infection by a bacteriophage requires the injection of the phage genome into the cytoplasm of the host bacterium. To achieve this, an infecting phage must traverse the layers of the host cell envelope, including the membrane(s) and the cell wall. This process is further complicated in bacterial species that produce a proteinaceous S-layer on the outermost surface of the cell. Surprisingly little is known about the mechanistic basis of these early stages in the phage lifecycle, and even less is known about infection of S-layer producing bacteria. Recent advances in structural biology, particularly in cryoEM, have dramatically improved our understanding of the structures of both bacterial S-layers and phage virions separately, but we still lack a molecular view combining both phage and S-layer in the process of infection. Here, we review our current understanding of phage-S-layer interactions, using the human pathogen Clostridioides difficile as an example host.

Clostridioides difficile↗

PubMed2026

Empirical Meropenem Versus Piperacillin/Tazobactam for Critically Ill Adults With Sepsis: Feasibility of a Randomised Trial.

BACKGROUND: Meropenem and piperacillin/tazobactam are commonly used empirical antibiotics in critically ill adults with sepsis, but whether one is superior to the other is uncertain. METHODS: The Empirical Meropenem versus Piperacillin/Tazobactam for Adult Patients with Sepsis (EMPRESS) trial is an ongoing investigator-initiated, randomised, open-label, adaptive clinical trial with an integrated feasibility phase comparing empirical treatment with meropenem versus piperacillin/tazobactam in critically ill adults with sepsis. The integrated feasibility phase enrolled 200 participants across 10 intensive care units (ICUs) in Denmark between 28 June and 12 December 2025. Five pre-specified feasibility criteria were evaluated; if all feasibility criteria were met, the trial would proceed unaltered, whereas failure to meet one or more criteria would require intervention and re-evaluation. RESULTS: We randomised 200 of 284 screened patients (70.4%). The median age was 70 years (interquartile range (IQR): 60-77), 65.5% were males. At randomisation, 80.0% received vasopressors or inotropes, and 43.5% were on invasive mechanical ventilation. Four of five pre-specified feasibility criteria were met: time to completion of the feasibility phase (5.5 months vs. threshold < 12.0 months), recruitment proportion (70.4% vs. threshold ≥ 50.0%), proportion of participants without consent to the continued collection of data (2.5% vs. threshold < 5.0%) and protocol adherence (81.0% vs. threshold ≥ 75.0%). The proportion of participants with timely primary outcome data availability (30-day mortality) within 45 days was 85.5% and below the pre-specified threshold of ≥ 95.0%. The proportions were low in the first 3 months (33.3%, 22.2% and 30.8%, respectively), increasing to 95.8% in the last month of the feasibility phase. All-cause mortality at 30 days was 30.5%, and specific serious adverse reactions occurred in 4.0% of participants. CONCLUSIONS: In this integrated feasibility evaluation of the EMPRESS trial comparing empirical meropenem versus piperacillin/tazobactam in critically ill adults with sepsis, four of five pre-specified feasibility criteria were met. The unmet criterion, timely primary outcome data availability, improved substantially during the feasibility phase. We consider the trial feasible and will proceed without modifications. EDITORIAL COMMENT: This feasibility study assessed recruitment, randomised allocation and data collection for the multicentre EMPRESS trial. For adaptive trials on trial platforms, careful interim checking of trial design functions is an important and necessary process. TRIAL REGISTRATION: Clinical Trials Information System EUCT number: 2023-509703-33-00; ClinicalTrials.gov identifier: NCT06184659; Universal Trial Number: U1111-1301-6379.

Humans↗

PubMed2026

A black soybean yoghurt fermented with a reusable probiotic cellulose gel: beneficial effects and metabolic characteristics.

The demand for plant-based yoghurts is continuously increasing. However, achieving stable physicochemical properties and acceptable flavor of the plant-based yoghurts remains challenging. In our previous work, we encapsulated Lactiplantibacillus plantarum (L. plantarum) LCC-605 biofilm into bacterial cellulose (BC), obtaining a LP605@BC gel. LP605@BC gel exhibited excellent harsh-environment resistance abilities and storage stability, and is very suitable as a starter culture. In this work, we used LP605@BC as a starter culture to prepare the fermented plant-based yoghurt (e.g., black soybean yoghurt, BSY-LP605@BC). After fermentation, the inverted nonflowing yoghurt was formed due to the strong interaction between protein and exopolysaccharide (EPS) produced by LCC-605 during fermentation. In addition, the water holding capacity (67.2%) of BSY-LP605@BC was also greatly improved. The viable bacterial counts in BSY-LP605@BC reached 11.2 log CFU/mL after 21 days of storage. BSY-LP605@BC showed increased antioxidant, cholesterol-lowering abilities, and hypoglycemic potential compared with the unfermented black soybean milk. Interestingly, LP605@BC could be reused at least 5 times, demonstrating excellent sustainability. Significant metabolomic differences between BSY-LP605@BC and the black soybean milk were observed via untargeted metabolomic analysis, further proving the beneficial effects of BSY-LP605@BC. Overall, our work developed an effective reusable starter culture for preparing the plant-based yoghurt in a sustainable manner, providing a new design direction and form of starter culture.

Yogurt↗

PubMed2026

Integrin-Linked Kinases 1, 4, and 5 participate in cell wall-mediated innate immunity to leaf and root pathogens.

The cell wall integrity (CWI) pathway is triggered by plasma membrane-localized receptors in plant cells and serves to orchestrate responses to cell wall damage by initiating compensatory changes under stressful environments. The essential role of CWI maintenance as part of plants' interactions with pests or pathogens and during growth is well known. Nevertheless, CWI pathways remain to be fully characterized. Here, we show that altered Integrin-Linked Kinase 1 (ILK1) expression causes widespread defects in the transcriptional program activated by the bacterial elicitor flg22, primarily in genes associated with cell wall integrity and immunity. These transcriptional deficiencies are recapitulated in mutant lines with altered ILK4 or ILK5 expression. Analysis of molecular and cellular defenses in ilk mutants revealed reduced callose accumulation in leaves treated with bacterial (elf18) and plant (pep1) elicitors and increased pathogen susceptibility. Histochemical analysis of cell-wall-associated staining across diverse cells and organs of ilk mutants revealed modified lignin-associated patterns in the root xylem and altered calcofluor staining patterns in the seed coat. All ilk mutants exhibited altered root morphology due to mechano-touch and high-NaCl stress. Based on these results, we propose that ILKs contribute to pathways connecting elicitor-triggered immune signaling with cell-wall-associated stress responses and that ILK-related defense functions may extend to the cotton root-nematode interaction, while the mechanism remains to be elucidated.

Cell Wall↗

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

Interface-dependent V. parahaemolyticus biofilm under varying temperatures, media, and oxygen conditions: implications for seafood safety.

Vibrio parahaemolyticus biofilms play a critical role in pathogen persistence in marine and seafood-processing environments, where oxygen availability, temperature, and surface interfaces vary widely. This study investigated biofilm development by three strains on partially submerged stainless-steel coupons under gas-liquid-wall (GLW) and fully submerged (SM) interfaces. Viable cell counts (log₁₀CFU/cm2) along with normalized protein concentration per viable cell (nProt) and normalized polysaccharide concentration per viable cell (nPol) were measured, under aerobic and anaerobic conditions across a temperature range of 15-30 °C, using tryptic soy broth with 3% NaCl (TSB) and seawater-based medium (SW). GLW biofilms consistently exhibited higher cell counts (6.4-7.3 log₁₀CFU/cm2) compared to SM biofilms (5.9-6.3 log₁₀CFU/cm2), suggesting that enhanced oxygen diffusion promotes bacterial proliferation. Conversely, SM biofilms exhibited significantly higher nProt and nPol levels (p < 0.001), indicating increased production of the extracellular polymeric substance (EPS) matrix under low-oxygen, high-nutrient conditions. Microscopy and three-dimensional surface plot analyses revealed relatively uniform biofilm layers at the GLW interface, whereas SM biofilms formed heterogeneous, tower-like structures. EPS production was further influenced by medium composition, oxygen, and temperature. SM biofilms grown in SW exhibited significantly higher nProt and nPol than those in TSB under aerobic conditions (p < 0.001), indicating enhanced matrix stabilization. Under anaerobic conditions at 15 °C, nProt and nPol were higher, whereas under aerobic conditions, peak nProt and nPol occurred at elevated temperatures. These findings highlight a trade-off between bacterial growth and matrix production and provide insight into biofilm adaptation and persistence in seafood-processing environments. These insights may help develop improved biofilm control and seafood safety management.

Biofilms↗

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

Genetic mutations driving ciprofloxacin resistance in laboratory-evolved Salmonella Typhimurium.

Ciprofloxacin resistance in Salmonella Typhimurium is a significant public health concern, and the mechanisms by which the resistance evolves are poorly defined. Here, by serial passaging under antibiotic selection, we isolated ciprofloxacin-resistant S. Typhimurium mutants and subjected them to whole-genome sequencing to reveal the major mutations associated with resistance. The Low CipR mutant acquired four chromosomal mutations in ramR, icdA, lipB, and gyrA, and the High CipR mutant gained additional mutations in gyrB, yaiC, and corA. Functional characterization determined that mutations in ramR resulted in efflux pump upregulation, while disruptions in the TCA cycle caused by mutations in icdA and lipB led to metabolic alterations. These changes indirectly enhanced resistance by increasing the expression of the global regulator MarA and reducing OmpF-dependent membrane permeability. Despite the observation of the G105A substitution in GyrA, enzymatic assays confirmed the failure to support resistance to ciprofloxacin, possibly because the structural alteration remained minimal. GyrB488-489dup was associated with maintained supercoiling under ciprofloxacin and enhanced fluoroquinolone resistance, suggesting a major role in resistance evolution. Other mutations in yaiC impaired biofilm and, in corA, intracellular accumulation of magnesium, possibly stabilizing the bacterial cell envelope under antibiotic pressure. The findings provide novel explanations for the multifaceted mechanisms leading to ciprofloxacin resistance in Salmonella and suggest targets to combat antimicrobial resistance.IMPORTANCEAntibiotic resistance in Salmonella Typhimurium is an increasing public health concern, yet the genetic changes that allow bacteria to become resistant are not fully understood. In this study, we evolved ciprofloxacin-resistant Salmonella in the laboratory and identified the mutations that arise during resistance development. We found that resistance does not result from a single change but from multiple adaptations affecting drug efflux, metabolism, and the antibiotic target. Some mutations increased the activity of pumps that remove antibiotics from the cell, while others altered bacterial metabolism and reduced membrane permeability, making it harder for the drug to enter. A duplication in the DNA gyrase subunit GyrB played a particularly important role in maintaining DNA function under antibiotic stress. Together, these results reveal how diverse genetic changes cooperate to generate ciprofloxacin resistance and provide insights that may help guide strategies to combat drug-resistant Salmonella infections.

DNA gyrase↗

PubMed2026

Spore-forming Clostridia as overlooked determinants of microbial risk in wastewater reuse systems.

Using treated municipal wastewater for crop irrigation is a key strategy to combat drought-induced water scarcity. However, current wastewater reclamation standards systematically underestimate risks from spore-forming pathogens. As highlighted in a recent minireview by A. Mrozinski, C. Le Maréchal, and E. Topp in Applied and Environmental Microbiology (92:e00173-26, 2026, https://doi.org/10.1128/aem.00173-26), Clostridioides difficile and Clostridium perfringens survive conventional disinfection, persist indefinitely in agricultural soils, and harbor critical antibiotic resistance genes. To safeguard the food supply and protect public health, regulatory frameworks must shift from relying solely on standard vegetative bacterial indicators and include monitoring resilient, spore-forming pathogens.

Clostridium↗

PubMed2026

Recovering membrane interaction kinetics of single molecules from 3D tracking data.

Interactions between cytosolic biomolecules and the bacterial inner membrane are fundamental to many cellular processes, yet directly measuring their binding kinetics in living cells remains challenging. Conventional 2D single-molecule tracking analyses can be insufficient, particularly when membrane association does not markedly alter the diffusion rate. Here, we present a method to recover membrane interaction kinetics from 3D single-molecule trajectories in rod-shaped bacteria. Using simulated 3D tracking data, we identify membrane-associated motion by quantifying how well short trajectory segments follow the circular curvature of the cell membrane. The resulting measure is further analyzed using a hidden Markov modeling framework, enabling robust discrimination between cytosolic and membrane-bound states and capturing the dynamics of state transitions without requiring diffusion-rate changes or direct colocalization with membrane markers. This work establishes a general framework for extracting membrane interaction kinetics from 3D single-molecule tracking data in live bacteria and highlights the value of realistic microscopy simulations for quantitative interpretation and systematic bias assessment.

Kinetics↗

PubMed2026

Boosting kynurenic acid in kombucha via substrate selection: metagenomic and biochemical insights.

Kombucha is gaining global popularity for its health benefits. This study explored the use of chestnut honey, a rich source of kynurenic acid (KYNA), to produce kombucha enriched with this metabolite. Five variants were prepared using different green/black tea blends and carbon sources: white sugar or acacia honey (controls) versus chestnut honey. Samples were analyzed for tryptophan metabolites, physicochemical properties, and microbial diversity. Komagataeibacter and Enterobacter were predominant bacterial genera in SCOBY. Candida and Aspergillus were predominated in the single sample analyzed for fungi. During fermentation, tryptophan decreased, while kynurenine increased. KYNA levels remained largely stable during fermentation and were mainly influenced by the fermentation substrate. No melatonin pathway derivatives were detected. On day 7, chestnut honey yielded kombucha with 381.680-739.915 μmol/L KYNA and elevated myricetin. Overall, chestnut honey-based kombucha represents a system in which substrate composition appears to be the main factor influencing KYNA levels in the final beverage.

Kynurenic Acid↗

PubMed2025

Depth-dependent multi-kingdom microbial interactions and biogeochemical cycling genes in eutrophic shallow lake sediments.

Microorganisms are pivotal to lake ecosystem biogeochemical cycles, yet existing research often focuses on single microbial kingdoms or surface sediments, neglecting multi-kingdom interactions and depth-resolved dynamics. To address these gaps, we used metagenomic sequencing to characterize microbial communities and their functional associations across overlying water and 0-45 cm sediments in four shallow lakes of the middle Yangtze River basin, China. Despite increasing bacterial and fungal diversity with depth, the 0-9 cm surface sediments exhibited the strongest multi-kingdom network connectivity and the greatest microbial stability. Functional genes exhibited clear depth-dependent patterns: nitrogen cycling genes, including those involved in dissimilatory nitrate reduction to ammonium, were most enriched in the upper 0-9 cm of sediment; methane cycling genes were positively correlated with depth; phosphorus cycling genes and some sulfur cycling genes, such as assimilatory sulphate reduction, declined with depth. Sediment microbial assembly was dominated by deterministic processes, in which the vertical distribution of functional genes was primarily dictated by heavy metals and conventional environmental indicators. These findings highlight depth-specific multi-kingdom microbial interactions and their associations with biogeochemical cycling, advancing lacustrine microbial ecology understanding and providing references for lake conservation under environmental change.

Lakes↗

PubMed2026

Spatially resolved multi-omics analysis of indigenous Bacillus-fortified high-temperature Daqu.

Layer-dependent patterns associated with indigenous Bacillus fortification on high-temperature Daqu remain unclear. Here, six indigenous functional Bacillus strains were combined to fortify Daqu at three inoculation levels (QH4, QH5, QH6), with non-fortified as the control (CK). Upper, middle, and lower shelf-layer samples were profiled by physicochemical measurements, volatilomics, organic acid analysis, untargeted metabolomics, 16S/ITS amplicon sequencing, and metagenomics. PERMANOVA showed significant effects of treatment, spatial layer, and their interaction on physicochemical, volatile, bacterial, and fungal profiles (P = 0.001). Among the three inoculation levels, QH5 showed the most balanced performance: QH5_M exhibited the highest observed mean peak temperature (63.3 °C; +4.5 °C relative to CK_M), and its group-mean temperature remained ≥ 60 °C for seven consecutive days. Multi-omics analyses indicated coordinated, non-linear, and layer-dependent differences associated with indigenous Bacillus fortification, with QH5_M showing the most pronounced combined thermal, pyrazine, substrate, microbial, and predicted functional profile. These findings indicate that moderate indigenous Bacillus fortification was associated with distinct layer-dependent thermal and flavor profiles and coordinated microbial, metabolic, and predicted functional differences.

Bacillus↗