npj Biofilms and Microbiomes最新文献

Plant-beneficial Pseudomonas and Bacillus have been extensively studied and applied in biocontrol of plant diseases. However, there is less known about their interaction within two-strain synthetic communities (SynCom). Our study revealed that Pseudomonas protegens Pf-5 inhibits the growth of several Bacillus species, including Bacillus velezensis. We established a two-strain combination of Pf-5 and DMW1 to elucidate the interaction. In this combination, pyoluteorin conferred the competitive advantage of Pf-5. Noteworthy, pyoluteorin-deficient Pf-5 cooperated with DMW1 in biofilm formation, production of metabolites, root colonization, tomato bacterial wilt disease control, as well as in cooperation with beneficial bacteria in tomato rhizosphere, such as Bacillus spp. RNA-seq analysis and RT-qPCR also proved the pyoluteorin-deficient Pf-5 mutant improved cell motility and metabolite production. This study suggests that the cooperative effect of Bacillus-Pseudomonas consortia depends on the balance of pyoluteorin. Our finding needs to be considered in developing efficient SynCom in sustainable agriculture.

Sarcopenia is a major health challenge due to an aging population. Probiotics may improve muscle function through gut-muscle axis, but their efficacy and mechanisms in treating sarcopenia remain unclear. This study investigated the impact of Bifidobacterium animalis subsp. lactis Probio-M8 (Probio-M8) on old mice and sarcopenia patients. We analyzed 43 subjects, including gut microbiome, fecal metabolome, and serum metabolome, using a multi-omics approach to assess whether Probio-M8 can improve sarcopenia by modulating gut microbial metabolites. Probio-M8 significantly improved muscle function in aged mice and enhanced physical performance in sarcopenia patients. It reduced pathogenic gut species and increased beneficial metabolites such as indole-3-lactic acid, acetoacetic acid, and creatine. Mediating effect analyses revealed that Probio-M8 effectively reduced n-dodecanoyl-L-homoserine lactone level in gut concurrent with increased creatine circulation, to significantly enhance host physical properties. These findings provide new insights into probiotics as a potential treatment for sarcopenia by modulating gut microbiota metabolism.

Bacterial biofilms are highly adaptable and resilient to challenges. Nutrient availability can induce changes in biofilm growth, architecture and mechanical properties. Their extracellular matrix plays an important role in achieving biofilm stability under different environmental conditions. Curli amyloid fibers are critical for the architecture and stiffness of E. coli biofilms, but how this major matrix component adapts to different environmental cues remains unclear. We investigated, for the first time, the effect of nutrient availability both on biofilm material properties and on the structure and properties of curli amyloid fibers extracted from similar biofilms. Our results show that biofilms grown on low nutrient substrates are stiffer, contain more curli fibers, and these fibers present higher β-sheet content and chemical stability. Our multiscale study sheds new light on the relationship between bacterial matrix molecular structure and biofilm macroscopic properties. This knowledge will benefit the development of both anti-biofilm strategies and biofilm-based materials.

In mucosal barriers, tissue cells and leukocytes collaborate to form specialized niches that support host-microbiome symbiosis. Understanding the spatial organization of these barriers is crucial for elucidating the mechanisms underlying health and disease. The gingiva, a unique mucosal barrier with significant health implications, exhibits intricate tissue architecture and likely contains specialized immunological regions. Through spatial transcriptomic analysis, this study reveals distinct immunological characteristics between the buccal and palate regions of the murine gingiva, impacting natural alveolar bone loss. The microbiota primarily affects gingival immunity in the buccal region. Additionally, a significant influence of the microbiota on the junctional epithelium facing the oral biofilm offers new insights into neutrophil recruitment. The microbiota also regulates the proliferation and barrier-sealing function of the gingival epithelium. This underscores the presence of immunological niches in the gingiva, with the microbiota differentially influencing them, highlighting the high complexity of this oral mucosal barrier.

Candidate phyla radiation (CPR) constitutes a substantial fraction of bacterial diversity, yet their survival strategies and biogeochemical roles in brackish-saline groundwater remain unknown. By reconstructing 399 CPR metagenome-assembled genomes (MAGs) and 2007 non-CPR MAGs, we found that CPR, affiliated with 44 previously proposed phyla and 8 putative novel phyla, played crucial roles in maintaining the microbial stability and complexity in groundwater. Metabolic reconstructions revealed that CPR participated in diverse processes, including carbon, nitrogen, and sulfur cycles. Adaption of CPR to high-salinity conditions could be attributed to abundant genes associated with heat shock proteins, osmoprotectants, and sulfur reduction, as well as their cooperation with Co-CPR (non-CPR bacteria co-occurred with CPR) for metabolic support and resource exchange. Our study enhanced the understanding of CPR biodiversity in high-salinity groundwater, highlighting the collaborative roles of self-adaptive CPR bacteria and their reciprocal partners in coping with salinity stress, maintaining ecological stability, and mediating biogeochemical cycling.

Melatonin (MT) (N-acetyl-5-methoxytryptamine) is an indoleamine recognized primarily for its crucial role in regulating sleep through circadian rhythm modulation in humans and animals. Beyond its association with the pineal gland, it is synthesized in various tissues, functioning as a hormone, tissue factor, autocoid, paracoid, and antioxidant, impacting multiple organ systems, including the gut-brain axis. However, the mechanisms of extra-pineal MT production and its role in microbiota-host interactions remain less understood. This review provides a comprehensive overview of MT, including its production, actions sites, metabolic pathways, and implications for human health. The gastrointestinal tract is highlighted as an additional source of MT, with an examination of its effects on the intestinal microbiota. This review explores whether the microbiota contributes to MT in the intestine, its relationship to food intake, and the implications for human health. Due to its impacts on the intestinal microbiota, MT may be a valuable therapeutic agent for various dysbiosis-associated conditions. Moreover, due to its influence on intestinal MT levels, the microbiota may be a possible therapeutic target for treating health disorders related to circadian rhythm dysregulation.

Previous research has established that the formation of Gardnerella vaginalis (GV) biofilm is one of the primary reasons for bacterial vaginosis (BV) recurrence. This study was the first to explore the impact of Streptococcus agalactiae (group B Streptococcus, GBS) on GV biofilm in a co-culture scenario. The results revealed that GBS could significantly increased the GV biomass in 48-hours dual-species biofilms. The luxS gene of GBS was significantly higher in dual-species biofilm, while knockdown of the luxS gene resulted in a significant decrease in mono- and dual-species biofilms. Meanwhile, in vitro addition of AI-2 (product of luxS gene) substantially increased biofilm biomass. Furthermore, we found that the expression of two genes related to biofilm formation was notably elevated in GV after receiving AI-2 signals. Collectively, these findings suggest that GBS enhances GV biofilm formation via luxS/AI-2 in an in vitro co-culture model, which in turn may promotes recurrence of BV.

The success of allogeneic hematopoietic cell transplantation (alloHCT) in curing hematologic disorders is limited by its short- and long-term toxicities. One such toxicity is oral mucositis (OM), causing pain, speech/swallowing difficulty, and prolonged hospitalization. Although conditioning chemoradiotherapy is the direct cause of OM, potential host-intrinsic mediators of mucosal injury remain elusive. We hypothesized that the oral microbiota may influence OM severity. We used a validated comprehensive scoring system based on specialized Oral Medicine examinations to longitudinally quantify OM severity in alloHCT recipients. High-throughput multi-site profiling of the oral microbiota was performed in parallel. We identify a sex-dependent commensal bacterium, Oribacterium asaccharolyticum, whose presence in saliva before transplantation is associated with more severe OM 14 days after transplantation. The sex predilection of this species correlated with higher uric acid levels in men. Our findings represent the first sex-dependent microbiota-mediated pathway in OM pathogenesis and introduce novel targets for preventative interventions.

The interaction between the gut-microbiota-derived metabolites and brain has long been recognized in both health and disease. The liver, as the primary metabolic organ for nutrients in animals or humans, plays an indispensable role in signal transduction. Therefore, in recent years, Researcher have proposed the Gut-Liver-Brain Axis (GLBA) as a supplement to the Gut-Brain Axis. The GLBA plays a crucial role in numerous physiological and pathological mechanisms through a complex interplay of signaling pathways. However, gaps remain in our knowledge regarding the developmental and functional influences of the GLBA communication pathway. The gut microbial metabolites serve as communication agents between these three distant organs, functioning prominently within the GLBA. In this review, we provide a comprehensive overview of the current understanding of the GLBA, focusing on signaling molecules role in animal and human health and disease. In this review paper elucidate its mechanisms of communication, explore its implications for immune, and energy metabolism in animal and human, and highlight future research directions. Understanding the intricate communication pathways of the GLBA holds promise for creating innovative treatment approaches for a wide range of immune and metabolic conditions.

The lower female reproductive tract (FRT) hosts a complex microbial environment, including eukaryotic and prokaryotic viruses (the virome), whose roles in health and disease are not fully understood. This review consolidates findings on FRT virome composition, revealing the presence of various viral families and noting significant gaps in knowledge. Understanding interactions between the virome, microbiome, and immune system will provide novel insights for preventing and managing lower genital tract disorders.