Interaction Of Microorganisms Research Articles

Spatiotemporal distribution, interactions and toxic effect of microorganisms and ARGs/MGEs from the bioreaction tank in hospital sewage treatment facility

Antibiotic resistance genes (ARGs) can be emitted from wastewater to ambient air and impose unignorable inhalable hazards, which could be exacerbated in antibiotic-concentrated hospital sewage. However, whether the ARG-carrying pathogens are more likely to infect cells remains largely unknown. Here, this study investigated and analyzed the spatiotemporal distribution, interaction, and toxicity of airborne microorganisms and their hosting ARGs in a hospital sewage treatment facility. The average concentration of ARGs/MGEs in sewage of bioreaction tank (BRT-W) was 2.27 × 104 gene copies/L. In the air of bioreaction tank (BRT-A), the average concentration of ARGs/MGEs was 15.86 gene copies/m3. In the four seasons, the ARGs concentration of sewage gradually decreased over time; The concentration of ARGs in the air first decreased and then increased. In spring, the concentration of ARGs/MGEs (qacedelta1-01) in BRT-W was highest (1.05 × 105 gene copies/L); The concentration of ARGs/MGEs (strB) in BRT-A in winter was higher than other seasons (26.18 gene copies/m3). Different from the past, this study also paid attention to the pathogenic potential of ARGs/MGEs in the air. The results of cell experiments showed that the cytotoxicity of drug-resistant Escherichia coli could reach Grade V. This suggested that the longer the drug-resistant E. coli were exposed to cells, the greater the cytotoxicity. Moreover, the cytotoxicity of bacteria increased with the increase in exposure time. In spring, the toxic effect of ARGs/MGEs in sewage of BRT-W was highest. Traceability analysis proved that BRT-W was an essential source of microorganisms and ARGs/MGEs in BRT-A. Furthermore, the combined risk of people exposed to the air of BRT in spring was higher than that in other seasons.

The Response of giving Gamal, Calliandra, and Lamtoro leaves compost fertilizer to Stevia plant (Stevia rebaudiana Bertoni) growth

Stevia (Stevia rebaudiana Bertoni) is a herbaceous plant, a sweet plant that can replace cane sugar. This plant is a shortday crop that can be harvested within 40-60 DAP. Compost is an organic fertilizer that is made by utilizing the weathering process from the interaction of microorganisms and decomposing bacteria. One of the litters can be utilized include gamal, calliandra and lamtoro. The purpose was to determine the effect of the three composts on the growth and productivity of the stevia. The analysis method used a completely randomized design (CRD) with one factor and four treatments. The results showed that compost had a significant effect on all observed variables including height, diameter, number of leaves, fresh weight and plant biomass. The highest growth and productivity of stevia plants were produced by stevia plants in treatment P3 (lamtoro compost), which influenced all observed aspects, including height and diameter (21.7 and 2 cm), number of leaves (152 leaves), total wet and dry weight (16.54 and 3.58). The lowest yields were produced in treatment P0 (control), which only increases the height and diameter by 5.81 and 1 cm, with only 60 leaves and 6.25 and 1.28 grams for dry and wet weights, respectively.

Characterization of harmful gases and bioaerosols of pig farms: a review of the existing literature

From the ecological and economic point of view, intensive pig farming is drawing more and more attention due to the appearance of harmful substances, which significantly increases the risks of air, water and soil pollution. In addition, the optimal criteria for the content of harmful gases, dust and microorganisms in the environment of pig farms are currently not clearly defined. In order to better understand the interaction of harmful emissions and aerosols, the article reviews data from the literature on their main components, concentrations, and interactions. The results showed that the main pollutants in pig farming are harmful gases (ammonia (NH3), carbon dioxide (CO2), methane (CH4), nitrogen oxide (N2O), hydrogen sulfide (H2S), which are released from manure. The presence of even small concentrations of harmful gases in farm air can cause respiratory and cardiovascular system disorders not only in animals, but also in humans. Along with harmful gases, it is important to control the emission of solid particles and dust from livestock premises, which can form aerosols. Microbial aerosols in pig houses contain bacteria, fungi, viruses, which mainly come from the animals themselves, manure or service personnel. The bioaerosol includes the Firmicutes and Bacteroidetes bacterial divisions and their derivatives. In addition, the content of potentially dangerous bacteria in the bioaerosol can reach up to 40 %. A major concern causes the presence of a large number of antibiotic-resistant microorganisms in the air of these farms (including MRSA). The existing strategies and methods to combat these problems are still imperfect and need to be refined. Currently, the interaction of harmful gases, dust, solid particles and microorganisms is not taken into account, which can increase the toxic effect of each other on the animal's body. Therefore, there is a need for a better understanding of these interactions in order to improve the strategy for improving the microclimate conditions by correcting the microbiota, finding and developing biological preparations that contain natural bacteria capable of neutralizing odors and disinfecting livestock premises.

Microbial community interactions determine the mineralization of soil organic phosphorus in subtropical forest ecosystems.

In subtropical forest ecosystems with few phosphorus (P) inputs, P availability and forest productivity depend on soil organic P (Po) mineralization. However, the mechanisms by which the microbial community determines the status and fate of soil Po mineralization remain unclear. In the present study, soils were collected from three typical forest types: secondary natural forest (SNF), mixed planting, and monoculture forest of Chinese fir. The P fractions, Po-mineralization ability, and microbial community in the soils of different forest types were characterized. In addition, we defined Po-mineralizing taxa with the potential to interact with the soil microbial community to regulate Po mineralization. We found that a higher labile P content persisted in SNF and was positively associated with the Po-mineralization capacity of the soil microbial community. In vitro cultures of soil suspensions revealed that soil Po mineralization of three forest types was distinguished by differences in the composition of fungal communities. We further identified broad phylogenetic lineages of Po-mineralizing fungi with a high intensity of positive interactions with the soil microbial community, implying that the facilitation of Po-mineralizing taxa is crucial for soil P availability. Our dilution experiments to weaken microbial interactions revealed that in SNF soil, which had the highest interaction intensity of Po-mineralizing taxa with the community, Po-mineralization capacity was irreversibly lost after dilution, highlighting the importance of microbial diversity protection in forest soils. In summary, this study demonstrates that the interactions of Po-mineralizing microorganisms with the soil microbial community are critical for P availability in subtropical forests.IMPORTANCEIn subtropical forest ecosystems with few phosphorus inputs, phosphorus availability and forest productivity depend on soil organic phosphorus mineralization. However, the mechanisms by which the microbial community interactions determine the mineralization of soil organic phosphorus remain unclear. In the present study, soils were collected from three typical forest types: secondary natural forest, mixed planting, and monoculture forest of Chinese fir. We found that a higher soil labile phosphorus content was positively associated with the organic phosphorus mineralization capacity of the soil microbial community. Soil organic phosphorus mineralization of three forest types was distinguished by the differences in the composition of fungal communities. The positive interactions between organic phosphorus-mineralizing fungi and the rest of the soil microbial community facilitated organic phosphorus mineralization. This study highlights the importance of microbial diversity protection in forest soils and reveals the microbial mechanism of phosphorus availability maintenance in subtropical forest ecosystems.

Analysis of Marchantia polymorpha-microorganism interactions: basis for understanding plant-microbe and plant-pathogen interactions.

Marchantia polymorpha is a bryophyte gaining significance as a model plant in evolutionary studies in recent years. This is attributed to its small-sequenced genome, standardized transformation methodology, global distribution, and easy and rapid in vitro culturing. As an evolutionary model, M. polymorpha contributes to our understanding of the evolution of plant defensive responses and the associated hormonal signaling pathways. Through its interaction with microorganisms, M. polymorpha serves as a valuable source of knowledge, yielding insights into new microbial species and bioactive compounds. Bibliographic analysis involved collecting, reading, and categorizing documents obtained from the Scopus and Web of Science databases using different search terms. The review was based on 30 articles published between 1995 and 2023, with Japanese and Spanish authors emerging as the most prolific contributors in this field. These articles have been grouped into four main themes: antimicrobial metabolites produced by M. polymorpha; identification and characterization of epiphytic, endophytic, and pathogenic microorganisms; molecular studies of the direct interaction between M. polymorpha and microorganisms; and plant transformation using bacterial vectors. This review highlights the key findings from these articles and identifies potential future research directions.

Long-term toxic effects of iron-based metal-organic framework nanopesticides on earthworm-soil microorganism interactions in the soil environment

With the widespread use of controlled-release nanopesticides in field conditions, the interactions between these nanopesticides and biological systems are complex and highly uncertain. The toxicity of iron-based metal organic frameworks (CF@MIL-101-SL) loaded with chlorfenapyr (CF) to terrestrial invertebrate earthworms in filter paper and soil environments and the potential mechanisms of interactions in the nanopesticide-earthworm-cornfield soil microorganism system were investigated for the first time. The results showed that CF@MIL-101-SL was more poisonous to earthworms in the contact filter paper test than suspension concentrate of CF (CF-SC), and conversely, CF@MIL-101-SL was less poisonous to earthworms in the soil test. In the soil environment, the CF@MIL-101-SL treatment reduced oxidative stress and the inhibition of detoxifying enzymes, and reduced tissue and cellular substructural damage in earthworms compared to the CF-SC treatment. Long-term treatment with CF@MIL-101-SL altered the composition and abundance of microbial communities with degradative functions in the earthworm intestine and soil and affected the soil nitrogen cycle by modulating the composition and abundance of nitrifying and denitrifying bacterial communities in the earthworm intestine and soil, confirming that soil microorganisms play an important role in reducing the toxicity of CF@MIL-101-SL to earthworms. In conclusion, this study provides new insights into the ecological risks of nanopesticides to soil organisms.

Predicting Microbiologically Influenced Concrete Corrosion in Self-Cleansing Sewers Using Meta-Learning Techniques

Sewer networks are not only necessary as an infrastructure for human societies, but they can also help humans achieve a stable situation with the surrounding natural environment by controlling and preventing the spread of pollution in the environment. As a result, concrete sewer maintenance and analysis of their damaging elements are critical. In this regard, modeling microbiologically influenced corrosion (MIC) is a challenging phenomenon. Due to the complicated aspects related to the interaction of microorganisms and concrete degradation, this research suggests several machine-learning models as well as traditional multiple linear regression model to predict the MIC in sewer pipelines. The models can be categorized into three sections: (i) stand-alone models (group method of data handling, generalized regression neural network, radial basis function neural network, multilayer perceptron neural network, chi-square automatic interaction detection, and classification and regression tree); (ii) integrative models (adaptive neuro-fuzzy inference system and support vector regression with particle swarm optimization, artificial bee colony, and firefly algorithm); and (iii) ensemble meta-learner stepwise regression (SR) model. After implementing the models, statistical measures, including root mean square error, mean absolute error, mean bias error, Pearson correlation coefficient, and Nash-Sutcliffe model efficiency are considered for evaluating models’ performances. The results indicate that the ensemble meta-learner-SR model is significantly more precise than other models. They also demonstrate that using an integrative model can improve the accuracy of stand-alone models by at least up to 42%. The durability and lifespan of the sewer system are also estimated with the aid of the best predictive model (meta-learner-SR) for two scenario cases of (i) gas phase and (ii) submerged conditions. It is concluded that the sewer systems have a considerably lower life span (24 y less) exposed to submerged sewage than the gas phase with 56 y of durability.

Editorial: Symbiotic interactions of algae and microorganisms: physiology and industrial applications

Editorial: Symbiotic interactions of algae and microorganisms: physiology and industrial applications

病原微生物–植物宿主互作中茉莉酸的多重功能

病原微生物–植物宿主互作中茉莉酸的多重功能

Root exudation under maize/soybean intercropping system mediates the arbuscular mycorrhizal fungi diversity and improves the plant growth.

Maize/soybean intercropping is a common cropping practice in Chinese agriculture, known to boost crop yield and enhance soil fertility. However, the role of below-ground interactions, particularly root exudates, in maintaining intercropping advantages in soybean/maize intercropping systems remains unclear. This study aimed to investigate the differences in root exudates between intercropping and monocropping systems through two pot experiments using metabolomics methods. Multiple omics analyses were conducted to explore correlations between differential metabolites and the community of Arbuscular Mycorrhizal Fungi (AMF), shedding light on the mechanisms underlying the dominance of intercropping from the perspective of root exudates-soil microorganism interactions. The study revealed that intercropping significantly increased the types and contents of root exudates, lowered soil pH, increased the availability of nutrients like available nitrogen (AN) and available phosphorus (AP), and enhanced AMF colonization, resulting in improving the community composition of AMF. Besides, root exudates in intercropping systems differed significantly from those in monocropping, with 41 and 39 differential metabolites identified in the root exudates of soybean/maize, predominantly amino acids and organic acids. The total amount of amino acids in the root exudates of soybean intercropping was 3.61 times higher than in monocropping. Additionally, the addition of root exudates significantly improved the growth of soybean/maize and AMF colonization, with the mycorrhizal colonization rate in intercropping increased by 105.99% and 111.18% compared to monocropping, respectively. The identified metabolic pathways associated with root exudates were closely linked to plant growth, soil fertility improvement, and the formation of AMF. Correlation analysis revealed a significant relationship (P < 0.05) between certain metabolites such as tartaric acid, oxalic acid, malic acid, aspartic acid, alanine, and the AMF community. Notably, the photosynthetic carbon fixation pathway involving aspartic acid showed a strong association with the function of Glomus_f_Glomerace, the dominant genus of AMF. A combined analysis of metabolomics and high throughput sequencing revealed that the root exudates of soybean/maize intercropping have direct or indirect connections with AMF and soil nutrients. This suggests that the increased root exudates of the soybean/maize intercropping system mediate an improvement in AMF community composition, thereby influencing soil fertility and maintaining the advantage of intercropping.

THE ROLE OF GUT MICROBIOTA IN IMMUNOMODULATION AND AUTOIMMUNE DISEASES: A COMPREHENSIVE REVIEW

The investigation into autoimmune conditions, particularly the intricate interplay between the gut microbiome and the immune response, has emerged as a critical domain of scholarly scrutiny. This review article provides a comprehensive analysis of prevailing views on the role of the gut microbiota in immune regulation and the development of autoimmune diseases. We begin this study by explaining the basic interactions of gut microorganisms and their relationship with the immune system. We then discuss dysbacteriosis and its implications for immune dysfunction, thus understanding the initiation of autoimmune reactions. Next, we delve into a section examining and reviewing clinical research findings identifying associations between differences in gut microbial compositions and various autoimmune diseases such as inflammatory bowel disease, rheumatoid arthritis, type 1 diabetes. In conclusion, this review addresses the methodological challenges that currently impede progress in this field and suggests approaches and plans for future research that may advance our understanding of the critical role played by the gut microbiota in the prevention, diagnosis, and treatment of autoimmune diseases. The article emphasizes the need to combine strategies to improve patient prognosis in cases of autoimmune diseases.

Phosphorus fertiliser application mitigates the negative effects of microplastic on soil microbes and rice growth

Soil microplastics (MPs) have attracted widespread attention recently. Most studies have explored how soil MPs affect the soil's physicochemical parameters, matter circulation, and soil microbial community assembly. Similarly, a key concern in agricultural development has been the use of phosphorus (P) fertiliser, which is essential for plant health and development. However, the relationship between MPs and phosphate fertilisers and their effects on the soil environment and plant growth remains elusive. This study assessed the influence of adding low-density polyethylene MPs (1%) with different phosphate fertiliser application rates on microbial communities and rice biomass. Our results showed that MPs changed the structure of soil bacterial and phoD-harbouring microbial communities in the treatment with P fertiliser at the same level and suppressed the interactions of phoD-harbouring microorganisms. In addition, we found that MPs contamination inhibited rice growth; however, the inclusion of P fertiliser in MP-contaminated soils reduced the inhibitory action of MPs on rice growth, probably because the presence with P fertiliser promoted the uptake of NO3--N by rice in MP-contaminated soils. Our results provide further insights into guiding agricultural production, improving agricultural management, and rationally applying phosphate fertilisers in the context of widespread MPs pollution and global P resource constraints.

Changes in Diversity and Composition of Rhizosphere Bacterial and Fungal Community between Resistant and Susceptible Pakchoi under Plasmodiophora brassicae

Plasmodiophora brassicae (P. brassicae) is a soil-born pathogen worldwide and can infect most cruciferous plants, which causes great yield decline and economic losses. It is not well known how microbial diversity and community composition change during P. brassicae infecting plant roots. Here, we employed a resistant and a susceptible pakchoi cultivar with and without inoculation with P. brassicae to analyze bacterial and fungal diversity using 16S rRNA V3-V4 and ITS_V1 regions, respectively. 16S rRNA V3-V4 and ITS_V1 regions were amplified and sequenced separately. Results revealed that both fungal and bacterial diversity increased, and composition was changed in the rhizosphere soil of the susceptible pakchoi compared with the resistant cultivar. In the four groups of R_mock, S_mock, R_10d, and S_10d, the most relatively abundant bacterium and fungus was Proteobacteria, accounting for 61.92%, 58.17%, 48.64%, and 50.00%, respectively, and Ascomycota, accounting for 75.11%, 63.69%, 72.10%, and 90.31%, respectively. A total of 9488 and 11,914 bacteria were observed uniquely in the rhizosphere soil of resistant and susceptible pakchoi, respectively, while only 80 and 103 fungi were observed uniquely in the correlated soil. LefSe analysis showed that 107 and 49 differentially abundant taxa were observed in bacteria and fungi. Overall, we concluded that different pakchoi cultivars affect microbial diversity and community composition, and microorganisms prefer to gather around the rhizosphere of susceptible pakchoi. These findings provide a new insight into plant–microorganism interactions.

Editorial: Bacterial wilt: pathogenic mechanism, disease control, bacteria-plant and bacteria-environmental microorganism interactions

Editorial: Bacterial wilt: pathogenic mechanism, disease control, bacteria-plant and bacteria-environmental microorganism interactions

Spatial metatranscriptomics resolves host–bacteria–fungi interactomes

The interactions of microorganisms among themselves and with their multicellular host take place at the microscale, forming complex networks and spatial patterns. Existing technology does not allow the simultaneous investigation of spatial interactions between a host and the multitude of its colonizing microorganisms, which limits our understanding of host–microorganism interactions within a plant or animal tissue. Here we present spatial metatranscriptomics (SmT), a sequencing-based approach that leverages 16S/18S/ITS/poly-d(T) multimodal arrays for simultaneous host transcriptome- and microbiome-wide characterization of tissues at 55-µm resolution. We showcase SmT in outdoor-grown Arabidopsis thaliana leaves as a model system, and find tissue-scale bacterial and fungal hotspots. By network analysis, we study inter- and intrakingdom spatial interactions among microorganisms, as well as the host response to microbial hotspots. SmT provides an approach for answering fundamental questions on host–microbiome interplay.

Microbial Interactions in Oral Biofilm: Evaluating Therapeutic Interventions and the Emergence of Resistance: A Narrative Review.

The oral cavity comprises numerous anatomical surfaces that are inhabited by a diverse array of bacteria, collectively forming a bacterial biofilm. Within this complex microbial community, certain bacterial species are etiologically linked to the development of common oral pathologies, such as dental caries and periodontitis, which stand as prominent instances of bacterial infections frequently encountered in clinical settings. Most biofilms are believed to be multispecies consortia. While single-species biofilms have been well-researched, mixed-species biofilms and their interactions amongst themselves have not drawn interest. The aim of the current review was to assess the various interactions of dual-species microorganisms in oral biofilm formation. Farnesol given exogenously for the treatment of biofilm can enhance or inhibit the growth of certain organisms, as seen in Candida albicans. In the age of antibiotic resistance, it is imperative to develop and uncover drugs capable of simultaneously targeting multiple species in order to mitigate antimicrobial resistance.

Community structure and niche differentiation of endosphere bacterial microbiome in Camellia oleifera.

Understanding the changes in bacterial community structure in different microenvironments of Camellia oleifera is essential to better explore the benign interaction between beneficial microorganisms and plants. Using Camellia oleifera trees, a Chinese wooden oil plant as a model ecosystem, we characterized the archaeal and bacterial microbiome across five different tissue-level niches using 16S rRNA gene analyses. Our research indicates that the diversity of Camellia oleifera endophytic bacterial communities is highly dependent on the plant compartment. The species replacement process (69.90%) is the dominant factor in the differences in bacterial community structure. The dominant bacteria phyla (Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Chloroflexi, and Verrucomicrobia) of Camellia oleifera show a significant plant compartment (roots, stems, leaves, fruits) enrichment effects. A variety of bacteria (Hymenobacter, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Mesorhizobium, Bradyrhizobium, Bacillus, Ochrobactrum, Pantoea, Pseudomonas, etc.) with nitrogen-fixed potentials are enriched in Camellia oleifera tissue. In addition, the hub bacterial groups of Camellia oleifera are Nitrospira, Haemophilus, Staphylococcus, Ruminiclostridium, and Ochrobactrum. They are widespread colonization in various tissues with a low relative abundance and may play an important role in the nitrogen cycle, host life promotion, and plant defense. This study provides a holistic understanding of the endosphere bacterial community structure, which is one of the most complete ecological niche-level analyses of Camellia oleifera. These results provide a scientific theoretical basis for an in-depth discussion of plant-endosphere microbial interaction and better exploration of benign interaction of beneficial microorganisms and plants.IMPORTANCEMicroorganisms inhabited various tissues of plants and play a key role in promoting plant growth, nutritional absorption, and resistance. Our research indicates that the diversity of Camellia oleifera endophytic bacterial communities is highly dependent on the plant compartment. Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Chloroflexi, and Verrucomicrobia are dominant bacteria phyla. The tissues of Camellia oleifera contain various bacteria with nitrogen fixation potential, host life promotion, and plant defense. This study provides a scientific theoretical basis for an in-depth discussion of plant-endosphere microbial interaction and better exploration of benign interaction of beneficial microorganisms and plants.

Microbe interactions drive the formation of floating iron films in circumneutral wetlands

Floating iron (Fe) films are widely found in wetlands that can form oxic-anoxic boundaries under circumneutral conditions. These films play a crucial role in the redox transformations and bioavailability of nutrients and trace metals. Current studies mainly focus on chemical oxidation during Fe film formation under circumneutral conditions. The functional microorganisms and associated microbial processes involved in Fe film formation have yet to be investigated in detail. Here, we investigated the microbial communities and involved microbial processes for the formation of floating Fe films in wetlands. Ferrihydrite was the dominant Fe(III) phase in films, accompanied by moderate levels of carbon and silicon. The Fe species and microbial analysis indicated that Fe films contain mixed-valent Fe and can form biotically. Microbial community analysis showed that the dominant genera in these Fe films were Fe-oxidizing and reducing bacteria and methanotrophs, including Leptothrix, Ferriphasclus, Gallionella, Geobacter and Methylococcales. Leptothrix, Ferriphasclus and Gallionella, as classical Fe(II)-oxidizing bacteria (FeOB), can oxidize Fe(II) with limited oxygen and form special structures that are consistent with Fe film morphology. Geobacter can provide a source of Fe(II) for FeOB growth, and Methylococcales can perform methane oxidation to provide energy for Fe cycling. The high ratios of Gallionella- and Geobacter-related microorganisms and carbon fixation genes proved the contribution of potential of Fe cycling and autotrophic microbial communities to the formation of Fe films. The diversity of microbial community suggested that Fe(II) oxidation could trigger carbon fixation, while Fe(III) reduction accelerated Fe and carbon cycling through anaerobic respiration and autotrophic chemosynthesis. These results highlight the contribution of these multiple microbial processes to Fe and carbon cycling during the formation of floating Fe films in wetlands. However, further studies are required to fully elucidate the interaction of functional microorganisms involved in floating film formation and their biogeochemical role in wetlands.

The Role of Bacteriophages in the Gut Microbiota: Implications for Human Health.

Bacteriophages (phages) are nano-sized viruses characterized by their inherent ability to live off bacteria. They utilize diverse mechanisms to absorb and gain entry into the bacterial cell wall via the release of viral genetic material, which uses the replication mechanisms of the host bacteria to produce and release daughter progeny virions that attack the surrounding host cells. They possess specific characteristics, including specificity for particular or closely related bacterial species. They have many applications, including as potential alternatives to antibiotics against multi-resistant bacterial pathogens and as control agents in bacteria-contaminated environments. They are ubiquitously abundant in nature and have diverse biota, including in the gut. Gut microbiota describes the community and interactions of microorganisms within the intestine. As with bacteria, parasitic bacteriophages constantly interact with the host bacterial cells within the gut system and have obvious implications for human health. However, it is imperative to understand these interactions as they open up possible applicable techniques to control gut-implicated bacterial diseases. Thus, this review aims to explore the interactions of bacteriophages with bacterial communities in the gut and their current and potential impacts on human health.

Microbubble Intensification of Bioprocessing

Microbubbles are famed for their large surface area-to-volume ratio, with the promise of intensification of interfacial phenomena, highlighted by more rapid gas exchange. However, for bioprocessing, it has been recognised for many decades that surfactant-rich fermentation media hinders mass transfer and possibly other interfacial processes due to surfactant loading on the interface. This article focuses on the roles of microbubble size and bubble bank, dispersed microbubbles that are sufficiently small to be non-buoyant, in mediating other modes of interfacial transfer via collisions with microorganisms and self-assembled clusters of microorganisms and microbubbles. These provide a more direct route of mass transfer for product gases that can be released directly to the microbubble with ~104 faster diffusion rates than liquid mediated gas exchange. Furthermore, secreted external metabolites with amphoteric character are absorbed along the microbubble interface, providing a faster route for liquid solute transport than diffusion through the boundary layer. These mechanisms can be exploited by the emerging fields of symbiotic or microbiome engineering to design self-assembled artificial lichen dispersed structures that can serve as a scaffold for the selected constituents. Additionally, such designed scaffolds can be tuned, along with the controllable parameters of microbubble mediated flotation separations or hot microbubble stripping for simultaneous or in situ product removal. Staging the product removal thus has benefits of decreasing the inhibitory effect of secreted external metabolites on the microorganism that produced them. Evidence supporting these hypotheses are produced from reviewing the literature. In particular, recent work in co-cultures of yeast and microalgae in the presence of a dispersed bubble bank, as well as anaerobic digestion (AD) intensification with dispersed, seeded microbubbles, is presented to support these proposed artificial lichen clusters.