搜索结果：Molecular microbiology

Antimicrobial resistance (AMR) is a major threat to global health. It reduces the effectiveness of current antibiotics and treatment for infectious diseases. The rise in AMR is mainly due to the overuse of antibiotics and the increased adaptability of harmful microorganisms. Among resistant bacteria, Methicillin-Resistant Staphylococcus aureus (MRSA) can resist an array of antibiotics. A key factor in resistance of MRSA is Penicillin-binding protein 2a (PBP2a). This protein decreases the effectiveness of β-lactam antibiotics and makes treatment more difficult. Therefore, finding new inhibitors that target PBP2a is crucial. In this study, Parmotrema perlatum, a himalayan lichen that has not been extensively studied for its antimicrobial properties, was chosen. Phytochemical research identified methyl orsellinate (MO) as a prominent secondary metabolite with antioxidant and antibacterial activities. However, initial docking analysis showed that MO had weak binding affinity for PBP2a. The molecular structure of MO was modified using a scaffold-morphing method to create a series of structural analogues. Molecular docking was conducted to assess their binding affinities and inhibitory potential. A detailed ADMET (Absorption, Distribution, Metabolism, Excretion, Toxicity) screening followed, to evaluate their pharmacokinetic and toxicity profiles. The stability of the top protein-ligand complexes using molecular dynamics (MD) simulations was assessed. MO-1 showed strong binding interactions with PBP2a and maintained stable trajectories throughout the simulation. Furthermore, MM/PBSA analysis indicated negative ΔG values, suggesting favourable binding. Overall, these results indicate that MO-derived analogue, MO-1 could be a computationally prioritised candidate for developing new therapies targeting MRSA. This study aims to open a new avenue to approach the problem of AMR with production of ethno-medicines using MO-1 to create effective therapies against MRSA and help reduce dependency on antibiotics.

Rapid and reliable identification of bacteria is essential in clinical and environmental microbiology. Gram staining remains a widely used method for preliminary classification; however, it may require additional steps and can be difficult to interpret under certain conditions. To address these limitations, we evaluated a modified potassium hydroxide (KOH) string test incorporating methylene blue to enhance visualization of DNA release and facilitate differentiation between Gram-positive and Gram-negative bacteria. A total of 185 samples from clinical and environmental sources (including hospitals, soil, salt mines and honeycombs) were analysed. Samples were first assessed using Gram staining and subsequently tested using the modified KOH method. In this procedure, a 3% KOH solution was applied to bacterial colonies, followed by the addition of methylene blue to improve visualization of filament formation. All Gram-negative isolates demonstrated visible string formation, while Gram-positive isolates showed no string formation, indicating complete concordance with Gram staining results within the tested dataset. Selected isolates were further examined using 16S rRNA gene analysis to support taxonomic identification. The modified KOH string test provides a rapid, simple and low-cost approach for preliminary bacterial differentiation. While it does not replace conventional or molecular identification methods, it may serve as a useful complementary tool, particularly in resource-limited or high-throughput laboratory settings.

Interstitial macrophages (IMs) are increasingly recognized for their vital roles in maintaining tissue homeostasis and orchestrating immune responses. Building on earlier work showing that two overarching IM subsets, CD206hi and CD206lo, encompass ten unique chemokine-expressing subpopulations that regulate immune cell recruitment and tertiary lymphoid structures, we sought to further define the molecular programs, potential divisions of labor, and spatial organization of murine lung IMs. We performed a comprehensive transcriptomic analysis of murine lung IMs and integrated these data with Xenium spatial transcriptomics to examine IM subset-associated gene programs and localization within the lung microenvironment. Differential gene expression across IM subsets is summarized in accompanying tables. CD206hi and CD206lo IM subsets exhibited distinct cytokine and receptor gene profiles, along with a predicted autocrine network that may influence their migration and cytokine-driven functions. IM subsets also displayed distinct innate immune signatures, including complement components, scavenger receptors, and pattern recognition receptors, such as Toll-like receptors and C-type lectins. Using Xenium spatial transcriptomics, we found that IMs in our dataset predominantly localized to three lung regions: bronchovascular bundles, interstitium, and periphery. CD206hi and CD206lo IMs preferentially occupied specific anatomical niches, associated with differential integrin and metallopeptidase gene expression. Chemokine expression within IMs also showed distinct spatial localization patterns associated with the positioning of T cells and B cells. Overall, our findings advance the understanding of IM heterogeneity and identify molecular programs associated with chemoattraction, inflammation regulation, innate immune defense, and tissue maintenance, while providing a high-resolution framework for investigating their localization, interactions, and contributions to lung immunity and disease.

Klebsiella pneumoniae expressing Extended-Spectrum-Beta-Lactamases (ESBLs) are a significant global public health challenge, affecting humans and livestock. However, the molecular epidemiology and relatedness between isolates from human and livestock reservoirs in Tanzania have not been well studied. This study aimed to address this knowledge gap by conducting a cross-sectional analysis in the Korogwe District, Tanzania. Klebsiella pneumoniae complex isolates were collected from children with and without diarrhoea and from chickens in commercial and smallholder farms. ESBL-positive isolates were subsequently tested for phenotypic resistance and analysed by whole-genome sequencing. ESBL-positive K. pneumoniae complex isolates were encountered from children with diarrhoea, 14% (n/N = 37/259), and 7% (n/N = 17/258) without diarrhoea. For chicken isolates, 10% (n/N = 38/371) of the commercial and 5% (n/N = 21/406) of the smallholder farms were ESBL-positive. The sequenced ESBL-positive isolates from humans and chickens comprised 73% (n/N = 69/95) K. pneumoniae, 14% (n/N = 13/95) K. quasipneumoniae subsp. quasipneumoniae, 13% (n/N = 12/95) K. quasipneumoniae subsp. similipneumoniae, and 1% (n/N = 1/95) K. quasivariicola. A broad variety of sequence types was observed, with 15 clusters of clonal identity identified, mostly in chickens from the same farm. Our findings also showed 68 isolates with 44 distinct capsular types. bla CTX-M-15 was the most commonly identified ESBL-expressing gene. In conclusion, the study highlights the possibility of interspecies transmission of ESBL-positive K. pneumoniae complex isolates between humans and chickens in the study area, emphasising the need for integrated One Health strategies to mitigate the spread of antimicrobial resistance in Tanzania.

In this Part 2 of a three-part review of advances in cobalt corrinoid research published between 2020 and 2025, we examine the biochemistry and microbiology of the cobalt corrinoids. Central to this literature is the chemical complementarity between cobalt and the corrin macrocycle, which enables distinct catalytic strategies including methyl transfer, radical rearrangement, reductive dehalogenation, and hybrid radical-SAM transformations. Recent work shows that corrinoid-dependent enzymes do not merely exploit intrinsic cobalt reactivity, but actively shape it through structural, electronic, and kinetic control over Co-C bond activation, intermediate stabilisation, and reaction selectivity. Equally prominent is the requirement for rigorous cofactor management, as corrinoid chemistry remains vulnerable to oxidative damage, misligation, and incomplete cofactor maturation, necessitating specialised systems for trafficking, remodelling, repair, and selective deployment. Genomic, evolutionary, and ecological studies further reveal that corrinoid metabolism is unevenly distributed, with widespread auxotrophy, selective transport, and cobamide exchange creating extensive metabolic interdependence within microbial communities. These patterns reflect evolutionary partitioning of biosynthetic capacity while emphasising the importance of environmental constraints, particularly cobalt availability and horizontal gene transfer, in shaping corrinoid cycling. In host-associated systems, corrinoid availability influences metabolic flux, microbial community structure, and functional outputs with implications for host physiology. Corrinoid metabolism emerges from this literature as a multiscale biological system in which inorganic chemistry, enzyme architecture, genomic organisation, and ecological context are functionally intertwined.

Banana production has suffered from Potyvirus musae (banana bract mosaic virus, BBrMV) in the Philippines and India; however, its occurrence and biological characteristics in Taiwan remain poorly understood. In this study, field surveys conducted between 2017 and 2018 identified 13 BBrMV-infected samples from commercial banana production areas in Taiwan. Among these, isolate F92 was successfully preserved by aphid transmission and used for further characterization. An infectious clone of BBrMV isolate F92 was constructed to establish a reliable inoculation system. In addition, poly(A) tail length was found to affect viral infectivity, and a longer poly(A) tail produced more consistent systemic infection. Using this system, the susceptibility of five banana cultivars commonly grown in Taiwan was evaluated. Most cultivars showed relatively mild symptoms and stable or declining viral accumulation, whereas the cultivar 'Rose' was more susceptible. This study reports the first infectious clone of BBrMV and provides a useful tool for evaluating cultivar susceptibility. Because BBrMV has not yet become widely established in Taiwan, these results may provide useful information for future disease management if the virus spreads in Taiwan.

The emergence of β-lactamase-producing bacteria is a critical global public health threat that undermines the efficacy of last-resort antibiotics. In Ethiopia, studies exploring resistance genes in drinking water systems are scarce. This study investigated bacterial profiles, antimicrobial susceptibility, and associated Extended-Spectrum β-Lactamase (ESBL) genes, including blaTEM, blaCTXM and blaSHV. A cross-sectional study was conducted between March 2023 and April 2024 by sampling raw, finished, reservoir, tap, and storage tank water in Addis Ababa. The samples were processed aseptically with routine microbiological culture and characterization methods. Antibiotic susceptibility testing was conducted using standardized Kirby-Bauer disc diffusion method as described by Clinical Laboratory Standards Institute (CLSI) version 33 guidelines. All data recorded were validated and then analyzed by Statistical Package for the Social Sciences version 25.0 Armonk. The associated parameters were compared using Fishers' exact test to determine their correlation. In all cases, a p-value less than or equal to 0.05 was considered statistically significant. From 45 samples, 94 bacterial species were characterized. Dominant isolates included E. coli (23.4%), Enterobacter spp. (16%), Citrobacter spp. (10.6%), K. pneumoniae (10.6%), Proteus spp. (8.5%), and Coagulase negative Staphylococcus species. Multi-drug resistant (MDR) is a non-susceptibility of an isolate to at least one antibiotic agent in three or more antimicrobial classes. Disc diffusion tests revealed that 63.8% (60/94) of isolates were MDR. The highest resistance levels were observed for ampicillin (86%), tetracycline (72.7%), cefuroxime (66.2%), and cefoxitin (53.5%). The principal MDR isolates were E. coli, Enterobacter, and Klebsiella species. Multiplex PCR on genomic DNA of MDR isolates showed a 26.6% (16/60) occurrence of ESBL genes; the combination of blaCTXM + blaTEM 11.7% (7/60) being the most frequent, followed by blaTEM (10%), blaCTXM (3.3%), and blaSHV (1.7%). In plasmid DNA of Gram-negative MDR isolates, ESBL genes occurred in 10.9% (6/54), with blaTEM (7.3%) being dominant, followed by blaCTXM (0.18%) and co-occurring blaSHV + blaTEM (0.18%). This study confirms the presence of ESBL genes in both the genomic and plasmid DNA of MDR bacteria in the water supply, particularly in storage tanks, tap and raw water. These findings indicate the transmission of β-lactamase-producing bacteria into drinking water supply systems. Regular monitoring, surveillance, and rigorous studies to identify contamination sources and mitigation strategies are urgently recommended.

The vermiform appendix was long considered a vestigial organ, yet accumulating evidence now supports its role as a component of gut associated lymphoid tissue and as a niche involved in microbial homeostasis and mucosal immune regulation. Against this background, whether appendectomy influences colorectal cancer (CRC) development and progression has become an important question at the intersection of oncology, microbiology, and immunology. Current epidemiological evidence does not support a simple model in which appendectomy uniformly increases long term overall CRC risk. Earlier observational studies, particularly from some Asian and American databases, suggested an increased risk in the short to intermediate period after surgery, but more recent prospective cohorts, molecular pathological epidemiology studies, and Mendelian randomization analyses indicate that this signal is highly dependent on time window and study design, and is more likely to reflect reverse causation and detection bias in the early postoperative period. At the same time, mechanistic and translational studies provide a biologically plausible framework, suggesting that appendectomy may be associated with changes in gut microbial communities, epithelial barrier function, inflammatory signaling, and tumor-associated macrophage-related immune programs, although much of the current evidence remains associative in humans or experimental in nature. Notably, appendectomy may not affect all CRCs in the same way, but may instead influence selected tumor locations and microbe related molecular subtypes, particularly Fusobacterium nucleatum (F. nucleatum) associated tumors. Overall, the relationship between appendectomy and CRC should be interpreted as a complex microbiota and immunity related issue rather than a simple unidirectional carcinogenic model. Future studies should clarify the true effects across different time windows, tumor subtypes, and immune ecological settings.

Polyethylene glycol (PEG) is widely used to improve the stability, solubility, and circulation half-life of nanoparticles, proteins, and small-molecule drugs. However, anti-PEG antibodies are increasingly recognized as a clinically relevant variable that can reshape the in vivo fate of PEGylated therapeutics, contributing to accelerated blood clearance, altered biodistribution, loss of efficacy, and, in a subset of individuals, hypersensitivity. This review integrates molecular, formulation, and host determinants of PEG immunogenicity using evidence from preclinical models and human studies. We summarize the prevalence and sources of pre-existing anti-PEG antibodies, including environmental exposure and host genetic associations, and discuss how antibody binding remodels the biomolecular corona, engages Fc- and complement-mediated pathways, and promotes phagocytic uptake that undermines PEG-mediated "stealth". We then evaluate mitigation strategies spanning polymer and lipid design, emerging PEG alternatives, and patient-centered approaches such as baseline antibody profiling and pre-treatment with free PEG in animal models. Finally, we highlight an emerging paradigm that exploits anti-PEG binding for benefit: bispecific anti-PEG antibodies and sequential pre-targeting strategies that convert PEG into a modular handle for active targeting across polymer nanoparticles, liposomes, and mRNA-lipid nanoparticles. Together, this review frames anti-PEG immunity as a central design variable in nanomedicine, linking PEG-mediated stealth, circulation time, targeting efficiency, biomolecular corona formation, and immune recognition. We propose guiding principles for deciding when PEG should be retained and optimized, replaced with alternative stealth materials, managed through patient-level screening or pre-treatment, or deliberately exploited as a modular handle for targeted delivery.

Brown seaweeds are among the richest marine sources of structurally diverse polysaccharides, especially fucoidan and alginate, which have attracted significant attention as multifunctional biomaterials for pharmaceutical, biomedical, and regenerative medicine applications. This review provides a comprehensive overview of extraction and purification methods, including conventional chemical, enzymatic, microwave-assisted, and ultrasound-assisted techniques, discussing how these methods affect yield, purity, molecular weight distribution, sulfation patterns, and structural integrity. An in-depth examination of the chemical structure of fucoidan and alginate highlights the importance of monosaccharide composition, sulfation degree, M/G ratio, molecular weight, and block arrangement in influencing bioactivity, gelation, biodegradability, and interactions with biological systems. The review thoroughly evaluates biocompatibility and biodegradation mechanisms, focusing on the roles of impurities, crosslinking density, oxidation levels, enzymatic degradation pathways, and environmental factors. It also summarizes recent advances in fucoidan- and alginate-based formulations, including hydrogels, nanoparticles, films, nanofibers, microspheres, sponges, injectable gels, and composite scaffolds, as well as key drug delivery mechanisms like ionotropic gelation, diffusion-controlled release, pH-responsiveness, mucoadhesion, and stimuli-responsive behaviors. By combining structural insights with emerging biomedical applications, this review highlights the remarkable versatility of fucoidan and alginate as next-generation marine biomaterials and explores their expanding potential in drug delivery, tissue engineering, wound healing, and multifunctional therapeutic systems.

Gastrointestinal disorders are a common complication following solid organ transplantation, but they also pose a real diagnostic challenge. There are many possible causes, ranging from immunosuppressive treatment toxicity to bacterial, parasitic, and viral infections. The use of syndromic molecular tests in microbiology has highlighted the important role played by enteric viruses, particularly norovirus, in the onset of diarrhea in transplant patients. These viruses, which are mostly benign in immunocompetent individuals, can cause severe and, above all, chronic infections responsible for significant morbidity and mortality and graft dysfunction. This review describes the characteristics of viral gastroenteritis in solid organ transplant patients, its epidemiology, pathophysiology, and clinical presentation. Finally, while the treatment of viral diarrhea is still based on symptomatic measures and the reduction of immunosuppression, it reviews the new specific antiviral therapies currently being evaluated. Overall, a better understanding of viral gastroenteritis in solid organ transplant patients is essential, as it is a major issue and diagnosis is crucial for appropriate management, at a time when the number of individuals with a functional transplant is increasing every year in France and worldwide.

Cadaver dissection remains fundamental in veterinary medicine and anatomy education, providing an irreplaceable experiential learning opportunity. It fosters three-dimensional anatomical understanding, the development of manual dissection skills, and early insights into clinical practice. Despite growing availability of digital and virtual simulation tools, preserved animal cadavers remain essential and are still preferred for anatomy teaching, surgical training, and diagnostic instruction. No alternative method reproduces anatomical structures with the same fidelity as a real cadaver. Preservation methods significantly affect teaching quality, occupational health for students, instructors, and staff, laboratory biosafety, and regulatory compliance. Traditional formaldehyde fixation effectively prevents tissue degradation and microbial growth; however, it is toxic, potentially carcinogenic, and impairs tissue color, flexibility, and realism. Saturated saline solutions have emerged as a low-cost, accessible, and pedagogically advantageous preservation option. The hyperosmotic environment delays autolysis and putrefaction while better preserving tissue texture, color, and joint mobility. However, saline does not sterilize cadavers, raising concerns about the potential persistence of halotolerant microorganisms, environmental contamination, and occupational exposure risks. This review synthesizes the literature on cadaver preservation in veterinary anatomy, focusing on biosafety and microbiological hazards. Emphasis is placed on preservation in saturated saline solution as a potentially promising alternative method, although long-term microbiological evidence remains limited and fragmented. The review examines evidence of bacterial and fungal contamination in cadavers, preservative solutions, laboratory surfaces, and fomites, particularly clinically relevant and potentially zoonotic pathogens. By integrating perspectives from anatomy education, microbiology, and occupational health, the review identifies knowledge gaps and highlights the need for standardized microbiological monitoring and biosafety protocols in laboratories adopting innovative preservation strategies.

Rivers are hotspots of global methane (CH4) emissions. We collected sediments from the upstream, midstream, and downstream reaches of the Wuxijiang River. Combined with anaerobic slurry incubation experiments and molecular biological techniques, we examined the spatial distribution of methanogenic pathways, as well as the abundance and community composition of methanogenic archaea. Results showed that hydrogenotrophic pathway (with H2 and CO2 as substrates) predominated across all reaches. The potential of this pathway reached its maximum in the middle reach. Quantitative PCR showed that mcrA gene abundance in the middle reach (1.44×108 copies·g-1) was significantly higher than that in the upper (9.18×107 copies·g-1) and lower reaches (1.01×108 copies·g-1). High-throughput sequencing indicated that the diversity of methanogenic archaea was significantly higher in the upper reach than in the middle and lower reaches, with community structure varying significantly among reaches. The methanogenic community in the upper and middle reaches was dominated by Methanoregula, Methanobacterium and Methanosarcina, whereas that in the lower reach was dominated by Methanoregula and Methanolinea. The relative abundance of Methanoregula showed an increasing trend from upstream (36.2%) to midstream (54.9%) and downstream (61.0%). Correlation analyses indicated that sediment organic carbon contents, NH4+-N contents, and pH were significantly associated with the spatial heterogeneity of methanogenic pathways and methanogenic archaeal community composition. Collectively, the midstream reach represented a potential hotspot of CH4 production in the Wuxijiang River, and these findings would provide new insights into the spatial heterogeneity of methane emissions in mountainous river system. 河流是全球甲烷(CH4)排放的热点区域之一。本研究以乌溪江上、中、下游河段沉积物为研究对象,通过室内厌氧泥浆培养试验及分子生物学技术,分析其产甲烷途径、产甲烷古菌丰度和群落组成的空间分布特征。结果表明:氢营养型(以H2和CO2为底物)是不同河段的优势产甲烷途径,且该途径的潜势在中游河段达到峰值,显著高于其他河段。定量PCR结果发现,中游河段的产甲烷古菌mcrA基因丰度(1.44×108 copies·g-1)显著高于上游(9.18×107 copies·g-1)和下游(1.01×108 copies·g-1)。高通量测序结果显示,上游河段产甲烷古菌多样性显著高于中游和下游,且不同河段产甲烷古菌的群落结构存在显著差异,上、中游河段群落组成以甲烷规则菌属、甲烷杆菌属和甲烷八叠球菌属为主,下游河段以甲烷规则菌属和甲烷绳菌属为主。其中,甲烷规则菌属的相对丰度由上游(36.2%)、中游(54.9%)至下游(61.0%)逐渐增加。相关性分析表明,沉积物有机碳、NH4+-N含量及pH是与产甲烷途径和产甲烷古菌群落组成空间异质性显著相关的关键环境因子。综上,中游河段是乌溪江CH4产生的潜在热点区域,研究结果有助于深入理解高山河流CH4排放的空间异质性特征。.

Mismatch repair deficiency (dMMR) and microsatellite instability (MSI-H) are rare in prostate cancer, occurring in 2%-4% of cases. These defects result in increased genomic instability and elevated tumor mutational burden (TMB), which can support responses to immune checkpoint inhibitors (ICIs). Here, we report a patient with locally advanced Gleason 5 + 5 = 10 prostatic adenocarcinoma harboring MSH2 and MSH6 genomic deletions with ultrahigh TMB (>250 mutations/megabase) in whom pembrolizumab resulted in a striking complete radiographic, pathologic, and molecular response. Using digital-spatial microscopy, single-cell RNA/T cell receptor (TCR) sequencing, and multiplex cytometry, we identify atypical tumor-infiltrating T cells with natural killer-like phenotypes and CD4+CD8+ (double-positive) lymphocytes. These clonal T cell populations expand preferentially following ICI and adopt terminally differentiated and cytotoxic profiles that may drive clinical response. Similar T cells are also present in diverse cancers and expand exclusively in ICI-responsive patients. These findings inform on the cellular mechanisms by which immunotherapies may mediate profound responses in patients with dMMR solid tumors.

Although fungi and bacteria commonly co-exist within polymicrobial communities, the molecular mechanisms underlying their interactions are still not well understood. Here, we show that the fungus Candida albicans forms biofilms with the bacterium Staphylococcus aureus along a nutritional axis of mutualism and propose that 'a copper economy' shapes fungal-bacterial biofilm interactions.Using in vitro biofilms formed on plastic, we found that dual-species biofilms are consistently larger than single-species counterparts, indicating a cooperative interaction. Dual-species proteomic analysis revealed non-reciprocal copper handling: C. albicans increased copper uptake via transporter Ctr1, while S. aureus enhanced copper export via regulator CsoR and export chaperone CopZ. Dual-species biofilms exhibited specific sensitivity to both copper depletion and supplementation, with corresponding reductions in biomass. We identified fungal copper import as the crucial element in mutualistic interactions between C. albicans and staphylococcal species. Moreover, fungal hyphae served as a critical scaffold for biofilm architecture, a role that was compromised under copper-replete conditions. Notably, copper nanoparticles disrupted these dual-species biofilms, highlighting a potential therapeutic avenue. Furthermore, we extend the role of C. albicans copper import to mutualistic interactions with additional bacterial species. Our findings establish copper as a central mediator of C. albicans and S. aureus cooperation and suggest that a 'copper economy' underpins mutualistic interactions in biofilms.

This study aimed to develop and evaluate a dual-drug-loaded PLGA nanoparticle system incorporating quercetin (QUE) and chlorhexidine (CHX) for localized, sustained delivery, with potential application in biofilm-associated pathologies. Single- and dual-drug systems containing CHX and QUE at different concentrations (1.5%, 5%, and 15%) were successfully loaded into poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) with high encapsulation efficiency. Physicochemical characterization was performed using dynamic light scattering (DLS), zeta potential analysis, SEM-EDX, FTIR, and thermal analysis (DSC and TGA). Release kinetics of QUE- and CHX-loaded nanoparticles were evaluated in an artificial saliva environment, and the amounts of CHX and QUE released were quantified by high-performance liquid chromatography (HPLC). Antimicrobial activity was assessed against Staphylococcus aureus and Escherichia coli using the disc diffusion method. The prepared nanoparticles displayed spherical morphology with sizes ranging from 54.08 to 356.1 nm and zeta potentials from - 2.11 to -12.46 mV, indicating colloidal stability. FTIR and thermal analysis confirmed molecular dispersion of drugs and polymer-drug interactions. QUE showed complete release within 168 h in the single-drug system, whereas co-loading with CHX extended QUE retention, with 20% remaining after 240 h. CHX release reached ∼80% in both formulations. CHX/QUE nanoparticles demonstrated superior antibacterial activity compared to QUE-only systems, effectively inhibiting both Gram-positive and Gram-negative bacteria. These compounds and formulations are designed for clinical applications due to their slow, controlled release of the dual-active PLGA NP system.

Diatom-derived polyunsaturated aldehydes (PUAs) significantly influence marine bacterial dynamics, yet the underlying proteomic mechanisms remain elusive. We employed high-resolution comparative proteomics to decipher the functional reprogramming of two bacterial communities-one naturally associated with a PUA-producing diatom (N-community) and another with a non-PUA producing (I-community)-under ecologically relevant PUA exposure. While growth rates and cell densities remained unaffected, indicating an absence of acute toxicity, proteomics revealed pronounced community-specific reorganization. N-community displayed stable, regulation-oriented adjustments consistent with physiological accommodation, whereas I-community exhibited dose-dependent stress responses at the endpoint of the growth curve, shifting toward protein repair and antioxidant defense. Our findings demonstrate that PUAs trigger profound proteomic reprogramming conditioned by the communities' prior ecological history. This functional divergence provides a molecular basis for understanding bacterial fitness and succession during diatom blooms, where PUA-mediated interactions could act as a selective filter shaping the phycosphere's microbial landscape.

Stress tolerance underpins ecological plasticity and niche expansion in fungi. Although Trichoderma is best known from sylvan, mycoparasitic, soil-, and plant-associated habitats, its occasional recovery from saline soils raises questions about the molecular basis of this adaptation. A coastal survey revealed limited but persistent Trichoderma diversity with frequent recovery of halotolerant T. asperelloides. Screening a salt-stressed T. asperelloides cDNA library in Saccharomyces cerevisiae identified 62 inserts, of which 12 were salt responsive in vivo. Deletion of gld1, encoding an aldo-keto reductase, impaired halotolerance and glycerol accumulation. In a 27-species synthetic community, the Δgld1 mutant was competitively displaced by other species under salinity. Cross-species promoter replacement in a salinity-sensitive strain T. atroviride increased its halotolerance. A global tef1 haplotype network placed the coastal isolates within broader T. asperelloides diversity, consistent with recurrent expansion into saline/coastal soils. Together, these findings link accessory-gene regulation to niche expansion in fungi.

Indigenous rhizobia that nodulate cowpea (Vigna unguiculata) can support inoculant development for semiarid farming systems, yet their 16S rRNA-based molecular diversity and symbiotic performance in Eastern Kenya remain poorly characterized. In this study, we isolated nodule-associated bacteria from cowpea root nodules collected from smallholder farms in Machakos and Kitui Counties and evaluated nodulation and plant growth under greenhouse conditions. We recovered 70 isolates and grouped them into 19 morphotypes on the basis of colony and biochemical traits, but only 15 isolates (21.4%) formed nodules. The authenticated isolates varied in nodulation (16.20 ± 1.39 to 51.70 ± 4.68 nodules plant-1) and total dry biomass under greenhouse conditions. The symbiotic efficiency ranged from 37.88 to 157.04% relative to the nitrogen-supplemented control, and eight isolates (53.3%) exceeded 100%. Three isolates (M-34, M-17, and M-27) presented the highest efficiencies (~140-157%) and outperformed the nitrogen-supplemented control and the reference strain (Bradyrhizobium sp. USDA 3456). Partial 16S rRNA sequencing assigned isolates to Rhizobium (53.3%), Bradyrhizobium (40.0%), and one isolate was affiliated with Mesorhizobium plurifarium, representing one of the first documented associations of this species with cowpea in Eastern Africa. Closely related isolates differed markedly in efficiency, indicating that taxonomic identity alone does not predict symbiotic performance. These results identify high-performing indigenous strains for further evaluation as candidates for field evaluation and future inoculant development.