Terminalia spp. (family Combretaceae) are widely used to treat a wide variety of ailments, including bacterial infections. The antibacterial activities of multiple Terminalia spp. have been verified experimentally. Several studies have reported inhibitory activity for Terminalia catappa L. against some bacteria, including a limited number of gastrointestinal pathogens. In contrast, the growth-inhibitory effects of several native Australian species against gastrointestinal pathogens have not yet been evaluated. This study screens the bacterial growth inhibition activity of T. catappa, T. microcarpa, T. muelleri, and T. canescens leaf extracts against a panel of gastrointestinal bacterial pathogens. Solvents with different polarities were used to extract different complements of phytoconstituents from the dried leaves. The T. canescens methanol extract displayed noteworthy activity against A. hydrophila and B. cereus (960µg/mL). In contrast, none of the ethyl acetate extracts prepared from any species tested displayed bacterial growth inhibitory activity. Notably, combinations of the Terminalia spp. extracts and selected conventional antibiotics yielded 15 synergistic, 59 additive, 79 non-interactive, and 29 antagonistic interactions. All the plant extracts were deemed to be nontoxic in human dermal fibroblast cell line assays, except the T. muelleri and T. microcarpa methanol extracts and the T. canescens water extract.

Metabolite-driven reprogramming of bacterial persisters: Mechanisms and therapeutic opportunities for overcoming antibiotic tolerance.

Selective anti-adhesion and anti-biofilm action of D-phenylalanine chiral nanofilms against Staphylococcus aureus.

The SPHK/S1P/S1PR axis promotes LPS challenge- and Edwardsiella piscicida infection-induced proinflammatory immune responses and bacterial killing activity in the head kidney macrophages of the Japanese flounder Paralichthys olivaceus

Type VI secretion systems (T6SSs) are molecular machines used by bacteria to release effectors that target either host cells, competing bacteria or fungi. Regulatory mechanisms underlying antifungal T6SS activity remain unexplored. Here we show, using mouse infection with wild-type and T6SS mutant bacteria, that T6SS activity of the enteropathogen, Yersinia pseudotuberculosis (Yptb), reduces fungal prevalence in the gut microbiota and has direct activity on Candida albicans. Screening of bacterial effector mutant strains, and structural and biochemical analyses identify TfeC as an antifungal chitinase T6SS effector that can kill C. albicans. In vivo experiments confirm that TfeC expression promotes Yptb colonization and reduces C. albicans abundance. We also show that Yptb senses the fungal quorum-sensing molecule, tyrosol, through the two-component system, EnvZ-OmpR, and responds by activating T6SS4. Our findings suggest that Yptb modulates its antifungal activities by detecting changes in fungal population density cues, revealing a mechanism of fungal-bacterial interkingdom communication mediated by fungal quorum-sensing molecules.

Contrasting community stability and functional dynamics of denitrifying anaerobic methane-oxidizers in rivers.

Phosphorus recovery from wastewater using waste gypsum via sulfur-metabolizing bacteria: Influence of gypsum type on performance and mechanisms.

Rice is one of the primary commodities cultivated by Indonesian farmers such as in the Tuban Regency. To increase rice productivity is critically important to evaluate the condition of soil fertility. Soil fertility assessment is needed to determine balanced fertilization. Balanced fertilization is critically essential in the production process. This research analysis method used the SOFIX database. The soil samples were carried out in rice fields based in one of the agriculture-integrated areas in the Tuban Regency. The results show that the soil had a deficient bacteria number and low nitrogen and phosphate circulation activities. On the other hand, all parameters such as total carbon, total potassium, total nitrogen, and total phosphorous also tend to be low. Therefore, applying balanced fertilization to recover soil fertility. Organic materials used to improve bacterial activities. The results suggest that paddy soil fertility status in Tuban Regency leads to recovery by adding organic materials.

The interaction between organic and inorganic nutrients, bacterial communities, and soil fertility has been well documented over time. Conventional agricultural systems heavily utilize both inorganic and organic fertilizers, each exerting distinct effects on soil microbial dynamics and plant growth. The objective of our experiments was to identify the most effective fertilization strategy for improving the biological quality of a microbiologically impoverished and low-productivity soil. To this end, four fertilization strategies were evaluated: (i) organic fertilizers characterized by a high content of organic carbon (Fertil 4-5-7-variant 1); (ii) organic fertilizers with 12% organic nitrogen from proteins (Bio Ostara N-variant 2) (iii) combined inorganic-organic fertilizers (P35 Bio-variant 3) and (iv) mineral (inorganic) fertilizers (BioAktiv-variant V4). This study aimed to assess the short-term effects of fertilizers with varying chemical compositions on the density of cultivable heterotrophic bacteria and their associated dehydrogenase (DH) activity in a petrocalcic chernozem soil containing pedogenic carbonates. Soil sampling was conducted according to a randomized block design, comprising four replicates per treatment (control plus four fertilizer types). The enumeration of cultivable bacteria was performed using Nutrient Agar and A2R Agar media, whereas dehydrogenase activity (DHA) was quantified based on the reduction of 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) to 1,3,5-triphenyl-tetrazolium formazan (TPF) by bacterial dehydrogenase enzymes. Marked differences were observed in both parameters between the plots amended with inorganic fertilizers and those treated with organic fertilizers, as well as among the organic fertilizer treatments of varying composition. The most pronounced increases in both bacterial density and dehydrogenase activity (DHA) were recorded in the plots receiving the fertilizer with a high organic nitrogen content. In this treatment, the maximum bacterial population density reached 6.25 log10 CFU g-1 dry soil after approximately two months (May), followed by a significant decline starting in July. In contrast, DHA exhibited a more rapid response, reaching its peak in April (42.75 µg TPF g-1 soil), indicating an earlier DHA activation of microbial metabolism. This temporal lag between the two parameters suggests that enzymatic activity responded more swiftly to the nutrient inputs than did microbial biomass proliferation. For the other two organic fertilizer variants, bacterial population dynamics were broadly similar, with peak densities recorded in June, ranging from 5.98 log10 CFU g-1 soil (V3) to 6.03 log10 CFU g-1 soil (V1). A comparable trend was observed in DHA: in V3, maximum DHA was attained in June (30 µg TPF g-1 soil), after which it remained relatively stable, whereas in V1, it peaked in June (24.05 µg TPF g-1 soil) and subsequently declined slightly toward the end of the experimental period. Overall, the temporal dynamics of bacterial density and DHA demonstrated a strong dependence on the quality and biodegradability of the organic matter supplied by each fertilizer. Both parameters were consistently lower under inorganic fertilization compared with organic treatments, suggesting that the observed increases in microbial density and activity were primarily mediated by the enhanced availability of organic substrates. The relationship between the density of culturable heterotrophic bacteria and dehydrogenase (DH) activity was strongly positive (r = 0.79), indicating a close functional linkage between bacterial density and oxidative enzyme activity. This connection suggests that the culturable fraction of the heterotrophic microbial community plays a key role in the early stages of organic matter mineralization derived from the applied fertilizers, particularly in the decomposition of easily degradable substrates.

Bacterial gene expression from sites of infection are poorly studied due to low levels of bacterial mRNA present in clinical samples. Here, we develop Transcript-Capture Seq, which uses customizable biotinylated probes generated in-house to enrich bacteria-specific RNA from host samples before Next Generation Sequencing (NGS). This method results in a >200-fold increase in bacterial mRNA reads from mixed samples and allows analysis of the complete bacterial transcriptome from clinical samples. We apply Transcript-Capture to models of tuberculosis (TB) infection as well as sputum samples from TB patients. TB patients exhibit unexplained heterogeneity in disease progression, and the activity of Mycobacterium tuberculosis (Mtb) has been proposed to affect treatment response. By applying Transcript-Capture to sputum samples collected from TB patients, we generate the first complete in vivo bacterial transcriptome of Mtb via NGS. Mtb from patient sputa shows upregulation of genes involved in host lipid utilization and zinc limitation, as well as a similar gene expression profile to Mtb log phase growth in vitro. Applying Transcript-Capture to clinical sputa provides a snapshot of bacterial activity directly from human patients and can be used to investigate the physiological state of bacteria surviving in vivo.

Rapid and accurate antimicrobial susceptibility testing (AST) is essential for guiding effective antibiotic therapy and combating antimicrobial resistance (AMR). Here, we present an instrument-free phenotypic AST method that integrates catalase-mediated hydrogen peroxide decomposition with microflow tubing displacement for naked-eye readout. The system employs a disposable syringe as the reaction chamber and a micrometer-scale PTFE tube as the displacement scale. Gas generated by bacterial catalase activity drives ink movement within the tubing, enabling visual discrimination between susceptible and resistant strains within ∼60 min. Using Escherichia coli and Staphylococcus aureus as model pathogens, we optimized bacterial inoculum size, hydrogen peroxide concentration, and incubation time to maximize sensitivity. Validation with 63 clinical isolates against four antibiotics following Clinical and Laboratory Standards Institute (CLSI) guidelines demonstrated high concordance with standard AST results. Furthermore, the method successfully distinguished susceptibility in 18 culture-free urinary tract infection samples. This low-cost, rapid, and portable platform has potential for point-of-care AST, particularly in resource-limited settings.

Background/Objectives: There is evidence of possible contamination of prosthetic components originating from dental laboratories. The aim of this study is to investigate the disinfectant effect of citric acid and polyethylene glycol on implant-prosthetic materials in comparison with an untreated control and chlorhexidine. Methods: A total of 720 disks made of three different materials (titanium grade V, zirconia coated with feldspathic ceramic, and PMMA) contaminated with three bacteria (Staphylococcus aureus, Enterococcus faecalis, and porphyromonas gingivalis) were analyzed. Four treatment groups were tested: citric acid, polyethylene glycol, chlorhexidine and an untreated control group. Two assessment periods (3 and 21 days of incubation) were used, with bacterial metabolic activity measured using the resazurin reduction test and then analyzed by electron microscopy. Results: The results show that chlorhexidine has a superior inhibitory effect on all materials and bacterial strains in the short-term evaluation (3 days), while citric acid and polyethylene glycol showed higher efficacy after 21 days. Citric acid also exhibits differential effects when applied to grade V titanium. These differences were statistically significant at p < 0.05. Conclusions: There is evidence to recommend chlorhexidine for the disinfection of laboratory prosthetic components, but the enhanced effect of citric acid on grade V titanium and its long-term efficacy make it clinically promising candidate.

Coupling microbial catalysis with electrochemical stimulation offers a promising strategy for heavy metal remediation. This study investigates how potentiostatic control influences the bioreduction of hexavalent chromium (Cr(VI)) by Bacillus cereus strain DIF1 in a bioelectrochemical system. Cr(VI) reduction was evaluated under various applied cathodic potentials, and the highest reduction efficiency (91.45%) was achieved at +0.04 V after 24 h. This performance significantly surpassed that of the abiotic control (82.55%) and the open-circuit biotic control (9.25%), indicating that the applied potential enhances microbial Cr(VI) reduction beyond contributions from abiotic processes alone. Cyclic voltammetry (CV) revealed a distinct redox feature at +0.04 V with no corresponding reverse peak, indicating kinetically favored electron transfer during Cr(VI) reduction under this condition. Microscopic imaging confirmed that, under the applied potential, Bacillus cereus DIF1 formed filamentous connections, exhibited higher chromium accumulation on bacterial cells than on the surrounding carbon paper electrode, and developed a robust biofilm on the cathode surface. The system maintained consistent Cr(VI) reduction performance over three consecutive cycles, demonstrating good short-term operational reproducibility. These findings highlight the critical role of precise electrochemical control in modulating microbial Cr(VI) reduction and provide mechanistic insights into the interplay between electrode potential and bacterial activity.

Intense training loads alter the skin microbiome and defence mechanisms in athletes, yet adaptation profiles remain insufficiently characterised. This study evaluated the relationships between skin bacterial microbiome structure, antimicrobial activity, dermcidin levels, and acne severity in male professional hockey players compared with amateur athletes and non-athletes. One hundred men (18–57 years) were examined and allocated to six subgroups by exercise intensity and acne status. Microbiota composition was assessed by culture-based methods and MALDI-TOF identification, antimicrobial activity measured spectrophotometrically, dermcidin quantified by ELISA, and sweat proteome characterised by HPLC-MS. Staphylococcus epidermidis and Micrococcus luteus predominated in all groups. Exercise intensity, rather than acne, was the main determinant of total bacterial colonisation, which increased approximately tenfold from non-athletes to professional hockey players. In non-athletes, higher antimicrobial activity correlated with greater acne severity, whereas in professionals this relationship was absent and dermcidin levels showed an inverse association with acne severity. Proteomic analysis identified 17 polypeptides; dermcidin and prolactin-inducible protein were dominant in all groups, and calprotectin (S100-A8/A9) was detected exclusively in healthy professionals.

Microbial induction of carbonate precipitation is common in nature, carbonic anhydrase (CA) secreted by microorganisms plays an important role in catalyzing the precipitation of CaCO3 from CO2. This study investigated how pH and temperature regulate microbial CA production, activity, and structure, and further examined their effects on CaCO3 deposition, steel slag carbon sequestration, and concrete crack healing. The results demonstrated that bacteria efficiently produced CA and maintained its activity over a broad range of alkaline pH levels and temperatures, the optimal conditions pH 9 and 30°C facilitated both bacterial CA production and activity by regulating growth and metabolism. Furthermore, pH and temperature modulated CA activity by altering its secondary structure (α-helices, β-turns) and weakening the enzyme’s active center for CO2 at higher pH, which consequently influenced CaCO3 deposition efficiency. The microbial treatment significantly enhanced carbon fixation in steel slag, with an 18.9% carbon sequestration rate at 48 hours, an 8% increase over the control group. In concrete crack-healing tests, the application of alkali-resistant microorganisms restored water permeability resistance to 93.24% of the original concrete after 28 d of healing. Microbial mineralization technology has great potential in steel slag carbon sequestration and self-healing concrete.

Sepsis-induced cardiac dysfunction is a major contributor to sepsis-related mortality, and many patients continue to experience long-term cardiac complications after recovery. Here, we demonstrate that cardiac senescence is a key feature of sepsis-associated cardiac dysfunction, with endothelial cells identified as the predominant senescent population in septic cardiac tissue. However, the pathogenic drivers of endothelial senescence in sepsis remain poorly characterized. Among potential mediators, we found that elevated levels of heme, a byproduct of hemolysis, strongly correlate with increased endothelial senescence and impaired cardiac function. Mechanistic studies revealed that heme acts as a novel ligand for STING, exacerbating bacterial infection-induced STING polymerization and activation, thereby promoting endothelial senescence. Notably, either STING inhibition or enhanced heme clearance via increased hemopexin expression significantly alleviated cardiac endothelial senescence and facilitated cardiac functional recovery in septic mice. These findings identify heme as a critical pathogenic driver of endothelial senescence and highlight heme clearance as a promising therapeutic strategy for mitigating sepsis-induced cardiac dysfunction.

Glutathione-responsive self-assembling peptide-coated Salmonella for antitumor therapy.

In this study, the authors focus on optimizing the processing parameters for the fabrication of biodegradable polymer filaments intended for subsequent 3D printing of biomedical structures and implants. Following extrusion and additive manufacturing, the produced materials underwent a comprehensive evaluation that included mechanical, microbiological, biofilm formation, and electron microscopy analyses. The complexity of these tests aimed to determine the potential of the developed materials for biomedical applications, particularly in the field of scaffold fabrication. At the initial stage, three types of filaments (technical designations 111, 145, and 146) were produced using Fused Filament Fabrication (FFF) technology. These filaments were based on a PLA/PHB matrix with varying types and concentrations of plasticizers. Standardized destructive tensile and compressive mechanical tests were conducted using an MTS Insight 1 kN testing system equipped with an Instron 2620-601 extensometer. Among the tested samples, the filament labeled 111, composed of PLA/PHB thermoplastic starch and a plasticizer, exhibited the most favorable mechanical performance, with a Young’s modulus of elasticity of 4.63 MPa for 100% infill. The filament labeled 146 had a Young’s modulus of elasticity of 4.53 MPa for 100% infill and the material labeled 145 had a Young’s modulus of elasticity of 1.45 MPa for 100% infill. Microbiological assessments were performed to evaluate the capacity of bacteria and fungi to colonize the material surfaces. During bacterial activity assessment, we observed biofilm formation on the examined sample surfaces of each material from the smooth and rough sides. The colony-forming units (CFUs) increased directly with the exposure time. For all samples from each material, the Log10 (CFU) value reached above 9.41 during 72 h of incubation for the activity of each type of bacteria (Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans). Scanning electron microscopy provided insight into the surface quality of the material and revealed its local quality and purity. Surface defects were eliminated by this method. Overall, the results indicate that the designed biodegradable filaments, especially formulation 111, have promising properties for the development of scaffolds intended for hard tissue replacement and could also be suitable for regenerative applications in the future after achieving the desired biological properties.

Protein circuits organize cell biology, but synthetic dynamics are challenging to engineer due to stochastic genetic and biochemical variation. Genetically encoded oscillators (GEOs) built from bacterial MinDE-family ATPases and activators generate synthetic protein waves that act as novel frequency-domain imaging barcodes in eukaryotic cells, providing a platform for understanding, engineering, and applying synthetic protein dynamics. Using budding yeast, we disentangle how expression levels and expression noise govern the GEO waveform and encodability. While the GEO amplitude is sensitive to extrinsic noise, the GEO frequency is stably encoded by the activator:ATPase ratio. By integrating GEO components into the yeast modular cloning toolkit, we developed different noise-guided expression strategies that act like filters on the GEO waveform. We paired these filters with hundreds of biochemically distinct GEO variants to engineer clonal populations that oscillate at distinct frequencies and to design waveform libraries with customizable spectral features and tunable waveform variation. Our work establishes a robust platform for precision genetic encoding of synthetic GEO oscillations and highlights the utility of noise-guided strategies for dynamic protein circuit design.

ObjectivesOpioid use during pregnancy is associated with adverse perinatal outcomes, but its effects on placental biology are not well understood. Because the placenta plays a vital role in fetal development and immune regulation, we examined how maternal opioid exposure influences microbial DNA signatures and immune gene expression in the placenta.MethodsPlacentas from opioid-exposed and control C57 BL/6 female mice were analyzed through 16S rRNA gene sequencing, bulk RNA sequencing and pathway enrichment analysis.ResultsOpioid-exposed placentas showed altered microbial DNA profiles, including increased α-diversity and enrichment of Staphylococcus spp. Transcriptomic analysis revealed 357 differentially expressed genes, emphasizing immune pathways, including dendritic cell-NK cell crosstalk, immunogenic cell death, and cytokine storm signaling. STAT3 signaling and heparan sulfate biosynthesis were downregulated. Pathways related to apoptosis, cytotoxicity, and neonatal death were upregulated.ConclusionsMaternal opioid exposure may disrupt placental microbial and immune environments, potentially leading to structural compromise through immune-mediated cellular apoptosis.