Publications by authors named "Sara C Bell"

Microbial diversity has been extensively explored in reef-building corals. However, the functional roles of coral-associated microorganisms remain poorly elucidated. Here, we recover 191 bacterial and 10 archaeal metagenome-assembled genomes (MAGs) from the coral Acropora kenti (formerly A.

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Article Synopsis
  • The sponge microbiome plays a crucial role in supporting sponge health by providing and recycling essential nutrients in environments where nutrients are scarce.
  • Research indicates that key microbial functions include carbohydrate degradation, carbon fixation, nitrogen and sulfur metabolism, and the provision of B-vitamins, although empirical validation of these functions is limited.
  • Sequencing of metagenomes and metatranscriptomes from three coral reef sponge species revealed important microbial activities, such as carbohydrate breakdown and carbon fixation, and showed that anaerobic nitrogen processes were more common than aerobic ones, highlighting discrepancies between predicted and observed microbial functions.
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Genetic signatures caused by demographic and adaptive processes during past climatic shifts can inform predictions of species' responses to anthropogenic climate change. To identify these signatures in , a reef-building coral threatened by global warming, we first assembled the genome from long reads and then used shallow whole-genome resequencing of 150 colonies from the central inshore Great Barrier Reef to inform population genomic analyses. We identify population structure in the host that reflects a Pleistocene split, whereas photosymbiont differences between reefs most likely reflect contemporary (Holocene) conditions.

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Chytridiomycosis has been a key driver of global frog declines and extinctions, particularly for high-altitude populations across Australia and the Americas. While recent evidence shows some species are recovering, the extent of such recoveries and the mechanisms underpinning them remain poorly resolved. We surveyed the historical latitudinal and elevational range of four Australian rainforest frogs that disappeared from upland sites between 1989 and 1994 to establish their contemporary distribution and elevational limits, and investigate factors affecting population recovery.

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Marine sponges often host diverse and species-specific communities of microorganisms that are critical for host health. Previous functional genomic investigations of the sponge microbiome have focused primarily on specific symbiont lineages, which frequently make up only a small fraction of the overall community. Here, we undertook genome-centric analysis of the symbiont community in the model species Ircinia ramosa and analyzed 259 unique, high-quality metagenome-assembled genomes (MAGs) that comprised 74% of the I.

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Corals and the reef ecosystems that they support are in global decline due to increasing anthropogenic pressures such as climate change. However, effective reef conservation strategies are hampered by a limited mechanistic understanding of coral biology and the functional roles of the diverse microbial communities that underpin coral health. Here, we present an integrated genomic characterization of the coral species Porites lutea and its microbial partners.

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Symbiotic bacterial communities resident on amphibian skin can benefit their hosts. For example, antibiotic production by community members can control the pathogen () and it is possible for these community members to be used as probiotics to reduce infection levels. In the early 1990s, the emergence of caused declines and disappearances of frogs in the Australian Wet Tropics; the severity of its effects varied among species and sites.

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Recent metagenomic analyses have revealed a high diversity of viruses in the pelagic ocean and uncovered clear habitat-specific viral distribution patterns. Conversely, similar insights into the composition, host specificity and function of viruses associated with marine organisms have been limited by challenges associated with sampling and computational analysis. Here, we performed targeted viromic analysis of six coral reef invertebrate species and their surrounding seawater to deliver taxonomic and functional profiles of viruses associated with reef organisms.

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Article Synopsis
  • Different types of frogs and toads have unique ways of growing up, and their skin helps them fight off germs.
  • Scientists studied 17 species at different stages of their lives to see how their skin protects them.
  • They found that frogs that grow slowly and spend a long time as tadpoles make more skin defenses to fight germs, while those that grow quickly focus more on growing up fast instead of making defenses.
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Pathogens can be critical drivers of the abundance and distribution of wild animal populations. The presence of an overdispersed pathogen load distribution between hosts (where few hosts harbour heavy parasite burdens and light infections are common) can have an important stabilizing effect on host-pathogen dynamics where infection intensity determines pathogenicity. This may potentially lead to endemicity of an introduced pathogen rather than extirpation of the host and/or pathogen.

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Emerging infectious diseases are contributing to global declines in coral reef ecosystems, highlighting a growing need for aetiological knowledge to develop effective management strategies. In this review, we focus on black band disease (BBD), one of the most virulent diseases and the only polymicrobial disease so far known to affect corals. A multipartite microbial consortium dominated by Cyanobacteria, but also including sulfur-cycling bacteria, other bacterial groups and members of the Archaea and Eukarya, forms a sulfide-rich anaerobic mat that migrates across the surface of coral colonies, killing the underlying tissues.

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Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is a widespread disease of amphibians responsible for population declines and extinctions. Some bacteria from amphibians' skins produce antimicrobial substances active against Bd. Supplementing populations of these cutaneous antifungal bacteria might help manage chytridiomycosis in wild amphibians.

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Rates of growth and reproduction of the pathogens that cause emerging infectious diseases can be affected by local environmental conditions; these conditions can thus influence the strength and nature of disease outbreaks. An understanding of these relationships is important for understanding disease ecology and developing mitigation strategies. Widespread emergence of the fungal disease chytridiomycosis has had devastating effects on amphibian populations.

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Background: Cystic fibrosis (CF) is a multi-system disease affecting multiple organs and cells besides the respiratory system. Metabolomic profiling allows simultaneous detection of biochemicals originating from cells, organs, or exogenous origin that may be valuable for monitoring of disease severity or in diagnosis.

Aim: We hypothesized that metabolomics using serum from children would differentiate CF from non-CF lung disease subjects and would provide insight into metabolism in CF.

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Certain bacteria present on frog skin can prevent infection by the pathogenic fungus Batrachochytrium dendrobatidis (Bd), conferring disease resistance. Previous studies have used agar-based in vitro challenge assays to screen bacteria for Bd-inhibitory activity and to identify candidates for bacterial supplementation trials. However, agar-based assays can be difficult to set up and to replicate reliably.

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Probiotic therapy through bioaugmentation is a feasible disease mitigation strategy based on growing evidence that microbes contribute to host defences of plants and animals. Amphibians are currently threatened by the rapid global spread of the pathogen, Batrachochytrium dendrobatidis (Bd), which causes the disease chytridiomycosis. Bioaugmentation of locally occurring protective bacteria on amphibians has mitigated this disease effectively in laboratory trials and one recent field trial.

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Many parasites and pathogens suppress host immunity to maintain infection or initiate disease. On the skin of many amphibians, defensive peptides are active against the fungus Batrachochytrium dendrobatidis (Bd), the causative agent of the emerging infectious disease chytridiomycosis. We tested the hypothesis that infection with the fungus may be linked to lower levels of defensive peptides.

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