Search Results (247)

Background: Gram-positive bacteria, once considered incapable of producing extracellular vesicles (EVs) due to their thick peptidoglycan layer, are now known to secrete EVs that transport virulence factors and modulate host immunity. These EVs contribute to bacterial pathogenicity by facilitating biofilm formation, immune evasion, and inflammation. Granulicatella adiacens, an oral commensal associated with infective endocarditis, represents a clinically relevant model to study EV-mediated virulence. Objectives: This study’s aim was to investigate whether the proteomic composition and immunomodulatory activity of G. adiacens EVs differ between biofilm and planktonic lifestyles, thereby contributing to distinct pathogenic behaviours. Methods: EVs isolated from G. adiacens CCUG 27809 cultures were characterized using nano LC-ESI-MS/MS, followed by comprehensive bioinformatic and cytokine assays. Results: Quantitative proteomic profiling identified 1017 proteins, revealing distinct signatures between biofilm- and planktonic-derived EVs. Principal component analysis showed clear segregation between the two states, with biofilm EVs enriched in proteins linked to stress adaptation, adhesion, and structural integrity, while planktonic EVs exhibited growth- and metabolism-related proteins. A total of 114 virulence-associated proteins were identified, including several novel candidates. Functionally, EVs from both conditions significantly induced pro-inflammatory cytokines IL-8 and IL-1β in a dose-dependent manner (p < 0.05), whereas IL-17 remained unchanged. Conclusions: G. adiacens EVs exhibit lifestyle-dependent proteomic and immunomodulatory differences, underscoring their role in host–pathogen interactions and endocardial infection. These findings provide a foundation for future mechanistic and in vivo studies exploring EV-mediated virulence and potential therapeutic modulation. Full article

Campylobacter hepaticus is the etiological agent of Spotty Liver Disease (SLD), a newly emerging bacterial disease of laying hens resulting in significant mortality and production losses primarily in free-range systems. Although its economic impact continues to grow, the molecular basis of C. hepaticus pathogenesis remains poorly understood. In this study, we conducted transcriptomic profiling of C. hepaticus in three host-relevant conditions, exposure to chicken bile, infection of a chicken liver hepatocellular carcinoma (LMH) cell line, and isolation from liver lesions of naturally infected chickens. Through RNA-seq analysis, we found unique gene expression signatures in each environment. In the bile, C. hepaticus exhibited differential expression of 412 genes, with upregulation of genes related to motility, cell envelope remodeling, glycosylation, nitrate respiration, and multidrug efflux systems, indicating a stress-adaptive, metabolically active lifestyle. In LMH, on the other hand, 125 genes were differentially expressed, primarily reflecting downregulation of motility, oxidative stress response, chaperones, and core metabolic processes, suggesting that these cells adopt a less active, intracellular dormant lifestyle. Transcriptomic analysis of C. hepaticus isolated from the liver identified 26 differentially expressed genes, featuring selective upregulation of genes associated with nitrate respiration, sulfur metabolism, and pyridoxal 5’ phosphate homeostasis, alongside downregulation of the major outer membrane porin (momp), stress response chaperones (dnaK, groL), and genes involved in oxidative stress defense and energy production. Furthermore, the immune evasion-related gene cmeA and a glycosyltransferase gene were found to be highly upregulated. This study presents the first in-depth transcriptomic exploration of C. hepaticus in multiple host relevant niches. Our findings reveal niche-specific gene expression profiles and highlight metabolic and structural adaptations that enable C. hepaticus to survive during bile exposure, persist within host cells, and contribute to liver pathology. These insights provide a basis for identifying novel virulence determinants and may inform the development of targeted interventions, including vaccines or antimicrobial therapy, to control SLD in commercial poultry operations. Full article

Hidradenitis suppurativa (HS) is a chronic, recurrent, and highly debilitating inflammatory disorder of the pilosebaceous unit. Its pathogenesis is considered multifactorial, involving genetic, environmental, hormonal, lifestyle, and microbiome-related factors. The microbiota, defined as the collection of microorganisms, their genomes, and their interactions within a given environment, colonizes multiple sites of the healthy human body, which include the skin and gut, where it contributes to the maintenance of homeostasis. In HS, both skin and gut microbiota exhibit disruptions in composition and diversity, a state referred to as dysbiosis. Alterations in the expression of antimicrobial peptides in HS further implicate the microbiome in disease pathophysiology. In addition, chronic inflammation, bacterial biofilm formation, and dysbiosis are thought to contribute to the severity and recurrence of HS. Although the precise role of dysbiosis in HS pathogenesis remains unclear, several studies have demonstrated a reduction in cutaneous microbial diversity in HS patients, distinguished by an increased abundance of anaerobic and opportunistic bacteria and a reduction in commensal species. The intestinal microbiome has been even less thoroughly investigated, but available evidence suggests decreased overall diversity and richness, with enrichment of pro-inflammatory and depletion of anti-inflammatory bacterial taxa. This review aims to provide an overview of the current knowledge regarding the role of the microbiome in HS, with the goal of informing the direction of future research, including the potential utility of the microbiome as a biomarker for diagnosis and severity stratification in HS. Full article

Wireworms are often referred as a hardly manageable group of pests due to their unstable lifestyle and uneven distribution in soils. The current strategy of wireworm control involves the heavy use of chemical pesticides. To find an effective and eco-friendly biological control agent against wireworms, evaluation of bacterial properties and insecticidal effects of six Bacillus thuringiensis (Bt) strains against Agriotes lineatus was performed under laboratory conditions. The presence of cry11, cyt2 and krsA gene was detected in Bt strain BHC 2.4, while the same strain had the ability to produce siderophores, protease, amylase and cellulase. Single inoculums of Bt strains (BHC 2.4; BHC 4.5; BHC 4.7; 1.5; 4.3; 6.1) showed mortality against Agriotes lineatus larvae in the range of 6.67–72.22%. However, the compatible Bt dual cultures showed significantly higher efficiency in comparison with the single inoculums, with the highest efficiency of 79.63% recorded for Bt strain BHC 2.4 + Bt strain 1.5. The efficiency of applied Bt strains might be associated with the presence of genes coding for antibiotics and toxins. Therefore, the use of selected Bt strains applied in a form of compatible mixes could offer a sustainable solution for wireworm management in wheat. Full article

The aging process, along with an inadequate diet and an inflammatory gut response resulting from dysbiosis, contributes to the pathogenesis of Alzheimer’s disease (AD). Modifying the composition of the gut microbiota through appropriate pre/probiotic-rich diets may act as a preventive option for AD. The variety of functions performed by the gut microbiota makes this ecosystem one of the most important systems in the human body. The Mediterranean diet (MedDiet), the Dietary Approaches to Stop Hypertension (DASH), the Mediterranean–DASH Intervention for Neurodegenerative Delay diet (MIND), and the modified ketogenic–Mediterranean diet (MKD) positively affect the intestinal microflora and may reduce the risk of dementia. A ketogenic diet has a neuroprotective effect and improves cognitive function but leads to a significant decrease in the abundance and diversity of bacterial species in favor of harmful bacteria. A Western-style diet (Western diet, WD) rich in processed products, red meat, simple sugars, and saturated fatty acids has a negative impact on gut microbiota function, increasing the risk of AD. Our review supports the hypothesis that factors like a proper diet and a healthy gut microbiota have a positive impact on the prevention of neurodegenerative diseases, including AD. A thorough understanding of the role the microbiota plays in the proper functioning of the nervous system can aid in the prevention of AD by developing new dietary strategies and dietary lifestyles. Full article

All forms of life on Earth are dependent on microbes. In vertebrates, the oral cavity and the gastrointestinal tract are colonized by large numbers of microorganisms, which includes species from many life forms: bacteria, fungi, archaea, and protozoa; this collection of microorganisms are commonly referred to as the microbiome. This article reviews the literature, providing a summary of oral and gastrointestinal microbial composition in health and during various disease states. Interactions are explored between microbes in the oral cavity and gastrointestinal tract. This study explores the influence of changed diet, lifestyle, and living conditions in order to examine the link between the oral and gastrointestinal microbiome and changes in their composition, and how this may affect human health. This study also investigates potential microbiome dysbiosis and disease causation in the space environment. The role of prebiotics, probiotics and postbiotics in oral health is discussed, with extension into the unexplored territory of probable oral and gastrointestinal bacterial population changes during long-duration (exportation class) space missions (ECSM). Full article

Bacillus cereus AS_3 and Bacillus cereus AS_5 are bacterial endophytes isolated from sterilized leaves of the medical plant Alectra sessiliflora, which were previously identified using 16S rRNA sequencing. Here, we present the whole-genome sequencing and annotation of strains AS_3 and AS_5, the first genome report of Bacillus cereus strains from A. sessiliflora. The genome of strain AS_3 has 59 contigs, 5 503 542 bp draft circular chromosome, an N₅₀ of 211,274 bp, and an average G+C content of 35.2%; whereas strain AS_5 has 38 contigs, 5,510,121 bp draft circular chromosome, an N₅₀ of 536,033 bp, and an average G+C content of 35.2%. A total of 5679 protein-coding genes, 62 genes coding for RNAs, and 122 pseudogenes in the strain AS_3 genome were identified by the National Center for Biotechnology Information Prokaryotic Annotation pipeline, whereas a total of 5688 gene protein-coding genes were identified in AS_5, with 60 genes coding for RNAs and 120 pseudogenes. Phenotypic analysis and whole-genome sequencing analysis showed that AS_3 and AS_5 share similar characteristics, including Gram-positive, motile, rod-shaped, and endospore-forming have shown a high sequence similarity with Bacillus cereus, type strain ATCC 14579^T. Strains AS_3 and AS_5 had genomic digital DNA–DNA hybridization (dDDH) with the type strain Bacillus cereus ATCC 14579^T of 85.8% and 86%, respectively, and average nucleotide identities (ANIs) of 98% and 98.01%, respectively. Phylogenomic analysis confirmed that strains AS_3 and AS_5 share very similar genomic and phenotypic characteristics, and are closely related to the type strain Bacillus cereus type strain ATCC 14579^T, supporting their classification within the Bacillus cereus species. A total of 10 secondary metabolite gene clusters, including siderophore type petrobactin, terpene type molybdenum cofactor, non-ribosomal peptide synthetase (NRPS) type bacillibactin, and β-lactone type fengycin, were predicted using AntiSMASH software (version 5.0). Putative genes potentially involved in bioremediation and endophytic lifestyle were identified in the genome analysis. Genome sequencing of Bacillus cereus AS_3 and Bacillus cereus AS_5 has provided genomic information and demonstrated potential biotechnological applications. Full article

Background/Objectives: An increasing number of apparently healthy individuals are adhering to a gluten-free lifestyle without any underlying medical indications, although the evidence for the health benefits in these individuals remains unclear. Although it has already been shown that a low- or gluten-free diet alters the gut microbiota, few studies have examined the effects of this diet on healthy subjects. Therefore, our aim was to evaluate whether and how a prolonged low-gluten diet impacts gut microbiota composition and function in healthy adults, bearing in mind its intimate link to the host’s health. Methods: Forty healthy volunteers habitually consuming a gluten-containing diet (HGD, high-gluten diet) were included in a randomised control trial consisting of two successive 8-week dietary intervention periods on a low-gluten diet (LGD). After each 8-week period, gut microbiota composition was assessed by 16S rRNA gene sequencing, molecular quantification by qPCR, and a cultural approach, while its metabolic capacity was evaluated through measuring faecal fermentative metabolites by ¹H NMR. Results: A prolonged period of LGD for 16 weeks reduced gut microbiota richness and decreased the relative abundance of bacterial species with previously reported potential health benefits such as Akkermansia muciniphila and Bifidobacterium sp. A decrease in certain plant cell wall polysaccharide-degrading species was also observed. While there was no major modification affecting the main short-chain fatty acid profiles, the concentration of the intermediate metabolite, ethanol, was increased in faecal samples. Conclusions: A 16-week LGD significantly altered both composition and metabolic production of the gut microbiota in healthy individuals, towards a more dysbiotic profile previously linked to adverse effects on the host’s health. Therefore, the evaluation of longer-term LDG would consolidate these results and enable a more in-depth examination of its impact on the host’s physiology, immunity, and metabolism. Full article

The emergence of antimicrobial resistance and the increasing demand for a healthier lifestyle have set new goals for science and industry. In the search for new, more effective, and environmentally friendly antimicrobial agents, special attention is being paid to natural resources. In this regard, essential oils derived from plants, which are widely used in the cosmetic, food, and pharmaceutical industries, are one of the solutions. In view of the above, this study aims to investigate the biological effects of Abies alba essential oil (AAEO). The chemical profile of AAEO was evaluated by GC/MS analysis, which revealed a high abundance of limonene (52.2%) and α-pinene (36.2%). Antioxidant activity evaluation showed a higher potential of AAEO in scavenging ABTS radical species with an IC₅₀ value of 1.18 ± 0.05 mg/mL. In vitro antimicrobial activity was determined by disc diffusion and minimum inhibitory concentration assays and showed that AAEO was more efficient in inhibiting the growth of G⁺ bacterial species. On contrary, in situ evaluations of antimicrobial effects of AAEO on different food models (strawberry, kiwi, white radish, and beetroot) resulted in more efficient suppression of G⁻ bacterial species. Although AAEO showed low effects on yeasts determined by in vitro methods, in situ investigations showed its higher potential in eradication of Candida yeast. The antibiofilm properties of the AAEO matrix were determined by means of crystal violet assay and MALDI-TOF MS Biotyper analysis against biofilm-forming Salmonella enterica. The analysis performed led to the conclusion that AAEO, when applied prior to biofilm formation, may contribute to the removal of planktonic cells and alter the abiotic surface, thereby reducing the suitability of Salmonella enterica for microbial attachment. Full article

Background: The gut microbiota plays a critical role in metabolic health and type 2 diabetes mellitus (T2DM). Alterations in microbial composition may influence glycemic control and systemic inflammation. Materials and methods: In this single-center, randomized study, 60 adults with T2DM receiving metformin were evaluated biologically and received either empagliflozin or sitagliptin. Demographic, metabolic, and lifestyle data were collected. Gut microbiota profiling was conducted at two timepoints to assess changes in bacterial and fungal taxa. Blood glucose, HbA1c, and inflammation markers were analyzed longitudinally. Results: Both treatment groups showed significant improvements in glycemic control. Median fasting glucose decreased from 132 to 123 mg/dL (p = 0.046) in the sitagliptin group and from 131 to 114 mg/dL (p = 0.025) in the empagliflozin group. Median HbA1c levels declined significantly in both groups, with a greater reduction in the empagliflozin group (p = 0.001 vs. p = 0.049). The microbiota analysis revealed an increase in beneficial bacteria (e.g., Bifidobacterium spp. and Lactobacillus spp.) and a decrease in pro-inflammatory taxa (Escherichia coli and Streptococcus spp.). Notably, empagliflozin was associated with a more pronounced microbiota rebalancing and a significant decline in fungal overgrowth (e.g., Candida spp.; p = 0.034). Conclusions: Treatment with sitagliptin and empagliflozin led to improved glycemic outcomes and partial restoration of gut microbial balance in T2DM patients. Empagliflozin showed superior efficacy in modulating both glycemia and dysbiosis. Full article

Skin aging is a complex process influenced by several factors, including UV exposure, environmental stressors, and lifestyle choices. The demand for effective, natural skincare products has driven research into plant-based oils rich in bioactive compounds. Rosehip oil has garnered attention for its high content of carotenoids, phenolics, and antioxidants, which are known for their anti-aging, photoprotective, and skin-rejuvenating properties. Despite the growing interest in rosehip oil, limited studies have investigated its efficacy on human skin using advanced imaging technologies. This study aims to fill this gap by evaluating the efficacy of cold-pressed Rosa canina seed oil on facial skin characteristics, specifically wrinkles, ultraviolet (UV) spot reduction, and erythema mitigation, using imaging technologies (the VISIA analysis system). Seed oil pressed from R. canina collected from the Băișoara area of Cluj County has been selected for this study due to its high carotenoid, phenolic, and antioxidant contents. The oil has also been analyzed for the content of individual carotenoids (i.e., lutein, lycopene, β Carotene, and zeaxanthin) using HPLC-DAD (High-Performance Liquid Chromatography—Diode Array Detector), along with lutein and zeaxanthin esters and diesters. After the preliminary screening of multiple Rosa species for carotenoid, phenolic, and antioxidant contents, the R. canina sample with the highest therapeutic potential was selected. A cohort of 27 volunteers (aged 30–65) underwent a five-week treatment protocol, wherein three drops of the selected rosehip oil were topically applied to the face daily. The VISIA imaging was conducted before and after the treatment to evaluate changes in skin parameters, including the wrinkle depth, UV-induced spots, porphyrins, and texture. Regarding the bioactivities, rosehip oil showed a significant total carotenoids content (28.398 μg/mL), with the highest levels in the case of the β-carotene (4.49 μg/mL), lutein (4.33 μg/mL), and zexanthin (10.88 μg/mL) contents. Results indicated a significant reduction in mean wrinkle scores across several age groups, with notable improvements in individuals with deeper baseline wrinkles. UV spots also showed visible declines, suggesting ideal photoprotective and anti-pigmentary effects attributable to the oil’s high vitamin A and carotenoid content. Porphyrin levels, often correlated with bacterial activity, decreased in most subjects, hinting at an additional antimicrobial or microbiome-modulatory property. However, skin responses varied, possibly due to individual differences in skin sensitivity, environmental factors, or compliance with sun protection. Overall, the topical application of R. canina oil appeared to improve the facial skin quality, reduce the appearance of age-related markers, and support skin health. These findings reinforce the potential use of rosehip oil in anti-aging skincare formulations. Further long-term, large-scale studies are warranted to refine dosing regimens, investigate mechanisms of action, and explore synergistic effects with other bioactive compounds. Full article

This review first provides an overview of the functional diversity of Orthoptera-associated microbiota and the services they provide to their hosts. However, data are widely scattered across the different families studied, making it difficult to establish whether a core microbiota is present. The abundance of some genera (Pantoea, Enterococcus, Enterobacter, Acinetobacter) is associated with the degradation of cellulose compounds, although their clear contribution remains to be determined. In addition, P. agglomerans may play a role in the production of aggregation pheromones in the desert locust. In terms of gut compartmentalisation, the diversity of the bacterial community in the foregut appears to be highly variable between individuals and species, whereas it is more uniform in other parts of the gut. Metabolic pathways of the gut microbiota revealed differences in amino acid metabolism between the midgut and hindgut. Bacteria in the midgut are associated with amino acid synthesis and anaerobic metabolism, whereas pathways in the hindgut may be involved in amino acid catabolism and ace-tyl-CoA-mediated processes. Further research is needed to better understand these different components of the bacterial community in digestive processes, and to identify bacterial species of particular interest in explaining species’ lifestyles or for bioconversion. Full article

Background/Objectives: Zuska disease is a rare inflammatory condition of the mammary gland, characterized by recurrent non-puerperal abscesses in the periareolar region, often complicated by fistula formation. It predominantly affects women who smoke, particularly perimenopausal women. This study aims to investigate the clinical features, treatment outcomes, and recurrence rates of Zuska disease in a cohort of patients. Methods: We conducted a retrospective analysis of 19 patients diagnosed with Zuska disease and treated at the Breast Surgery Clinic of San Martino Policlinic Hospital between January 2021 and June 2024. Data were collected on demographics, clinical presentation, imaging findings, surgical interventions, intraoperative cultures, and postoperative outcomes. The types of surgeries performed, antibiotic therapy regimens, and histological findings were recorded. Results: The mean age of the patients was 43.8 years. The most common presentation was a painful breast mass without fistula formation (12 patients), signs of a past abscess with negative preoperative ultrasound findings (five patients), and abscesses with fistulas (two patients). Intraoperative cultures revealed a range of bacterial species. Recurrence occurred in five patients (26%), and reoperation was required in three cases. All patients were free of symptoms at follow-up, with an average recurrence time of 13.6 months. Conclusions: Zuska disease presents significant treatment challenges due to its recurrent nature. While surgical interventions, such as abscess drainage and ductal excision, are effective, recurrence remains common, particularly in patients with risk factors like smoking. A personalized therapeutic approach, tailored to each patient’s clinical profile, is essential to improving long-term outcomes. Early diagnosis, timely surgical management, and lifestyle modifications play a crucial role in reducing recurrence. Future studies should focus on optimizing treatment protocols and developing individualized strategies for managing comorbidities. Full article

All animals have outsourced about half of the 20 proteinogenic amino acids (AAs). We recently demonstrated that the loss of biosynthetic pathways for these outsourced AAs is driven by energy-saving selection. Paradoxically, these metabolic simplifications enabled animals to use costly AAs more frequently in their proteomes, allowing them to explore sequence space more freely. Based on these findings, we proposed that environmental AA availability and cellular respiration mode are the two primary factors determining the evolution of AA auxotrophies in animals. Remarkably, our recent analysis showed that bacterial AA auxotrophies are also governed by energy-related selection, thereby roughly converging with animals. However, bacterial AA auxotrophies are highly heterogeneous and scattered across the bacterial phylogeny, making direct ecological and physiological comparisons with the animal AA outsourcing model challenging. To better test the universality of our model, we focused on Bdellovibrionota and Myxococcota—two closely related bacterial phyla that, through aerobic respiration and a predatory lifestyle, best parallel animals. Here, we show that Bdellovibrionota, driven by energy-related selection, outsourced a highly similar set of AAs to those in animals. This sharply contrasts with Myxococcota, which exhibit far fewer AA auxotrophies and rarely show signatures of energy-driven selection. These differences are also reflected in Bdellovibrionota proteomes, which are substantially more expensive than those of Myxococcota. Finally, we found evidence that the expression of costly proteins plays a crucial role in the predatory phase of the Bdellovibrio life cycle. Together, our findings suggest that Bdellovibrionota, through their obligate predatory lifestyle, exhibit the closest analogy to the AA auxotrophy phenotype observed in animals. In contrast, facultative predation, as seen in Myxococcota, appears to substantially limit the evolution of AA auxotrophies. These cross-domain convergences strongly support the general validity of our AA outsourcing model. Full article

Bacterial viruses (phages) are abundant and ecologically impactful, but laboratory-based experimental model systems vastly under-represent known phage diversity, particularly for ssDNA phages. Here, we characterize the genomes and infection properties of two unrelated marine flavophages—ssDNA generalist phage phi18:4 (6.5 Kbp) and dsDNA specialist phage phi18:1 (39.2 Kbp)—when infecting the same Cellulophaga baltica strain #18 (Cba18), of the class Flavobacteriia. Phage phi18:4 belongs to a new family of ssDNA phages, has an internal lipid membrane, and its genome encodes primarily structural proteins, as well as a DNA replication protein common to ssDNA phages and a unique lysis protein. Phage phi18:1 is a siphovirus that encodes several virulence genes, despite not having a known temperate lifestyle, a CAZy enzyme likely for regulatory purposes, and four DNA methyltransferases dispersed throughout the genome that suggest both host modulation and phage DNA protection against host restriction. Physiologically, ssDNA phage phi18:4 has a shorter latent period and smaller burst size than dsDNA phage phi18:1, and both phages efficiently infect this host. These results help augment the diversity of characterized environmental phage–host model systems by studying infections of genomically diverse phages (ssDNA vs. dsDNA) on the same host. Full article