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Microbiology (Reading, England) May 2023In microbiome research, considerable effort has been invested in finding core microbiomes, which have been hypothesized to contain the species most important for host...
In microbiome research, considerable effort has been invested in finding core microbiomes, which have been hypothesized to contain the species most important for host function. Much less attention has been paid to microbiome members that are present in only a subset of hosts. Such accessory microbiomes must in large part consist of species that have no effect on fitness, but some will have deleterious effects on fitness (pathogens), and it is also possible that some accessory microbiome members benefit an ecologically distinct subset of hosts. This short paper discusses what we know about accessory microbiomes, specifically by comparing it with the concept of accessory genomes.
Topics: Microbiota
PubMed: 37167086
DOI: 10.1099/mic.0.001332 -
Frontiers in Cellular and Infection... 2020Asthma is a group of inflammatory conditions that compromises the airways of a continuously increasing number of people around the globe. Its complex etiology comprises... (Review)
Review
Asthma is a group of inflammatory conditions that compromises the airways of a continuously increasing number of people around the globe. Its complex etiology comprises both genetic and environmental aspects, with the intestinal and lung microbiomes emerging as newly implicated factors that can drive and aggravate asthma. Longitudinal infant cohort studies combined with mechanistic studies in animal models have identified microbial signatures causally associated with subsequent asthma risk. The recent inclusion of fungi in human microbiome surveys has revealed that microbiome signatures associated with asthma risk are not limited to bacteria, and that fungi are also implicated in asthma development in susceptible individuals. In this review, we examine the unique properties of human-associated and environmental fungi, which confer them the ability to influence immune development and allergic responses. The important contribution of fungi to asthma development and exacerbations prompts for their inclusion in current and future asthma studies in humans and animal models.
Topics: Animals; Asthma; Fungi; Humans; Hypersensitivity; Infant; Microbiota; Mycobiome
PubMed: 33324573
DOI: 10.3389/fcimb.2020.583418 -
Proceedings. Biological Sciences Mar 2020Phylosymbiosis was recently formulated to support a hypothesis-driven framework for the characterization of a new, cross-system trend in host-associated microbiomes....
Phylosymbiosis was recently formulated to support a hypothesis-driven framework for the characterization of a new, cross-system trend in host-associated microbiomes. Defining phylosymbiosis as 'microbial community relationships that recapitulate the phylogeny of their host', we review the relevant literature and data in the last decade, emphasizing frequently used methods and regular patterns observed in analyses. Quantitative support for phylosymbiosis is provided by statistical methods evaluating higher microbiome variation between host species than within host species, topological similarities between the host phylogeny and microbiome dendrogram, and a positive association between host genetic relationships and microbiome beta diversity. Significant degrees of phylosymbiosis are prevalent, but not universal, in microbiomes of plants and animals from terrestrial and aquatic habitats. Consistent with natural selection shaping phylosymbiosis, microbiome transplant experiments demonstrate reduced host performance and/or fitness upon host-microbiome mismatches. Hybridization can also disrupt phylosymbiotic microbiomes and cause hybrid pathologies. The pervasiveness of phylosymbiosis carries several important implications for advancing knowledge of eco-evolutionary processes that impact host-microbiome interactions and future applications of precision microbiology. Important future steps will be to examine phylosymbiosis beyond bacterial communities, apply evolutionary modelling for an increasingly sophisticated understanding of phylosymbiosis, and unravel the host and microbial mechanisms that contribute to the pattern. This review serves as a gateway to experimental, conceptual and quantitative themes of phylosymbiosis and outlines opportunities ripe for investigation from a diversity of disciplines.
Topics: Animals; Bacteria; Host Specificity; Microbiota; Phylogeny; Plants; Symbiosis
PubMed: 32126958
DOI: 10.1098/rspb.2019.2900 -
BMJ Open Ophthalmology Jun 2022In this review, we aim to summarise key articles that explore relationships between the gut and ocular surface microbiomes (OSMs) and immune-mediated dry eye. The gut... (Review)
Review
In this review, we aim to summarise key articles that explore relationships between the gut and ocular surface microbiomes (OSMs) and immune-mediated dry eye. The gut microbiome has been linked to the immune system by way of stimulating or mitigating a proinflammatory or anti-inflammatory lymphocyte response, which may play a role in the severity of autoimmune diseases. Although the 'normal' gut microbiome varies among individuals and demographics, certain autoimmune diseases have been associated with characteristic gut microbiome changes. Less information is available on relationships between the OSM and dry eye. However, microbiome manipulation in multiple compartments has emerged as a therapeutic strategy, via diet, prebiotics and probiotics and faecal microbial transplant, in individuals with various autoimmune diseases, including immune-mediated dry eye.
Topics: Anti-Inflammatory Agents; Autoimmune Diseases; Dry Eye Syndromes; Gastrointestinal Microbiome; Humans; Microbiota
PubMed: 36161855
DOI: 10.1136/bmjophth-2021-000956 -
Current Opinion in Pediatrics Dec 2021Asthma is the most common chronic disease of childhood. Investigations of the lower and upper airway microbiomes have significantly progressed over recent years, and... (Review)
Review
PURPOSE OF REVIEW
Asthma is the most common chronic disease of childhood. Investigations of the lower and upper airway microbiomes have significantly progressed over recent years, and their roles in pediatric asthma are becoming increasingly clear.
RECENT FINDINGS
Early studies identified the existence of upper and lower airway microbiomes, including imbalances in both associated with pediatric asthma. The infant airway microbiome may offer predictive value for the development of asthma in later childhood, and it may also be influenced by external factors such as respiratory viral illness. The airway microbiome has also been associated with the clinical course of asthma, including rates of exacerbation and level of control. Advances in -omics sciences have enabled improved identification of the airway microbiome's relationships with host response and function in children with asthma. Investigations are now moving toward the application of the above findings to explore risk modification and treatment options.
SUMMARY
The airway microbiome provides an intriguing window into pediatric asthma, offering insights into asthma diagnosis, clinical course, and perhaps treatment. Further investigation is needed to solidify these associations and translate research findings into clinical practice.
Topics: Asthma; Child; Humans; Infant; Microbiota; Respiratory System
PubMed: 34412069
DOI: 10.1097/MOP.0000000000001054 -
Frontiers in Cellular and Infection... 2023Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected a substantial portion of the world's population, and novel consequences of COVID-19 on the... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected a substantial portion of the world's population, and novel consequences of COVID-19 on the human body are continuously being uncovered. The human microbiome plays an essential role in host health and well-being, and multiple studies targeting specific populations have reported altered microbiomes in patients infected with SARS-CoV-2. Given the global scale and massive incidence of COVID on the global population, determining whether the effects of COVID-19 on the human microbiome are consistent and generalizable across populations is essential.
METHODS
We performed a synthesis of human microbiome responses to COVID-19. We collected 16S rRNA gene amplicon sequence data from 11 studies sampling the oral and nasopharyngeal or gut microbiome of COVID-19-infected and uninfected subjects. Our synthesis included 1,159 respiratory (oral and nasopharyngeal) microbiome samples and 267 gut microbiome samples from patients in 11 cities across four countries.
RESULTS
Our reanalyses revealed communitywide alterations in the respiratory and gut microbiomes across human populations. We found significant overall reductions in the gut microbial diversity of COVID-19-infected patients, but not in the respiratory microbiome. Furthermore, we found more consistent community shifts in the gut microbiomes of infected patients than in the respiratory microbiomes, although the microbiomes in both sites exhibited higher host-to-host variation in infected patients. In respiratory microbiomes, COVID-19 infection resulted in an increase in the relative abundance of potentially pathogenic bacteria, including .
DISCUSSION
Our findings shed light on the impact of COVID-19 on the human-associated microbiome across populations, and highlight the need for further research into the relationship between long-term effects of COVID-19 and altered microbiota.
Topics: Humans; COVID-19; SARS-CoV-2; RNA, Ribosomal, 16S; Microbiota; Gastrointestinal Microbiome
PubMed: 37600938
DOI: 10.3389/fcimb.2023.1211348 -
BioTechniques Jul 2018To what extent can your microbiome define you and how can it be altered to optimize your health?
To what extent can your microbiome define you and how can it be altered to optimize your health?
Topics: Gastrointestinal Microbiome; Health; Humans; Microbiota
PubMed: 30014735
DOI: 10.2144/btn-2018-0091 -
MSystems Oct 2022The diversity and functional significance of microbiomes have become increasingly clear through the extensive sampling of Earth's many habitats and the rapid adoption of...
The diversity and functional significance of microbiomes have become increasingly clear through the extensive sampling of Earth's many habitats and the rapid adoption of new sequencing technologies. However, much remains unknown about what makes a "healthy" microbiome, how to restore a disrupted microbiome, and how microbiomes assemble. In December 2019, we convened a workshop that focused on how to identify potential "rules of life" that govern microbiome structure and function. This collection of mSystems Perspective pieces reflects many of the main challenges and opportunities in the field identified by both in-person and virtual workshop participants. By borrowing conceptual and theoretical approaches from other fields, including economics and philosophy, these pieces suggest new ways to dissect microbiome patterns and processes. The application of conceptual advances, including trait-based theory and community coalescence, is providing new insights on how to predict and manage microbiome diversity and function. Technological and analytical advances, including deep transfer learning, metabolic models, and advances in analytical chemistry, are helping us sift through complex systems to pinpoint mechanisms of microbiome assembly and dynamics. Integration of all of these advancements (theory, concepts, technology) across biological and spatial scales is providing dramatically improved temporal and spatial resolution of microbiome dynamics. This integrative microbiome research is happening in a new moment in science where academic institutions, scientific societies, and funding agencies must act collaboratively to support and train a diverse and inclusive community of microbiome scientists.
Topics: Humans; Microbiota
PubMed: 36073805
DOI: 10.1128/msystems.00583-22 -
American Journal of Clinical Dermatology Sep 2020Advances in sequencing, bioinformatics and analytics now allow the structure, function and interrelations of whole microbial communities to be studied in greater detail.... (Review)
Review
Advances in sequencing, bioinformatics and analytics now allow the structure, function and interrelations of whole microbial communities to be studied in greater detail. Collaborative efforts and multidisciplinary studies, crossing the boundary between environmental and medical microbiology, have allowed specific environmental, animal and human microbiomes to be characterized. One of the main challenges for microbial ecology is to link the phylogenetic diversity of host-associated microbes to their functional roles within the community. Much remains to be learned on the way microbes colonize the skin of different living organisms and the way the skin microbiome reacts to the surrounding environment (air, water, etc.). In this review, we discuss examples of recent studies that have used modern technology to provide insights into microbial communities in water and on skin, such as those in natural resources (thermal spring water), large mammals (humpback whales) and humans (the skin microbiome). The results of these studies demonstrate how a greater understanding of the structure and functioning of microbiota, together with their interactions with the environment, may facilitate the discovery of new probiotics or postbiotics, provide indicators for the quality of the environment, and show how changes in lifestyle and living environment, such as urbanization, can impact on the skin microbiome and skin health and disease in humans.
Topics: Animals; Humans; Humpback Whale; Microbiota; Phylogeny; Skin; Water Microbiology
PubMed: 32910439
DOI: 10.1007/s40257-020-00551-x -
Microbiome Aug 2023A growing body of evidence suggests that the gut microbiota is strongly linked to general human health. Microbiome-directed interventions, such as diet and exercise, are... (Meta-Analysis)
Meta-Analysis
BACKGROUND
A growing body of evidence suggests that the gut microbiota is strongly linked to general human health. Microbiome-directed interventions, such as diet and exercise, are acknowledged as a viable and achievable strategy for preventing disorders and improving human health. However, due to the significant inter-individual diversity of the gut microbiota between subjects, lifestyle recommendations are expected to have distinct and highly variable impacts to the microbiome structure.
RESULTS
Here, through a large-scale meta-analysis including 1448 shotgun metagenomics samples obtained longitudinally from 396 individuals during lifestyle studies, we revealed Bacteroides stercoris, Prevotella copri, and Bacteroides vulgatus as biomarkers of microbiota's resistance to structural changes, and aromatic and non-aromatic amino acid biosynthesis as important regulator of microbiome dynamics. We established criteria for distinguishing between significant compositional changes from normal microbiota fluctuation and classified individuals based on their level of response. We further developed a machine learning model for predicting "responders" and "non-responders" independently of the type of intervention with an area under the curve of up to 0.86 in external validation cohorts of different ethnicities.
CONCLUSIONS
We propose here that microbiome-based stratification is possible for identifying individuals with highly plastic or highly resistant microbial structures. Identifying subjects that will not respond to generalized lifestyle therapeutic interventions targeting the restructuring of gut microbiota is important to ensure that primary end-points of clinical studies are reached. Video Abstract.
Topics: Humans; Microbiota; Gastrointestinal Microbiome; Biomarkers; Diet; Life Style
PubMed: 37553697
DOI: 10.1186/s40168-023-01604-z