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Francis, W.

Publications and source records attributed to Francis, W..

3 recordsLinked to original sources

Orion Microbiome Database: mapping constellations in the microbiome universe

BackgroundPublicly available microbiome sequencing data have grown rapidly in scale and diversity, but secondary use remains limited by fragmentation across repositories, inconsistent annotations, heterogeneous processing pipelines, and incomplete metadata. These barriers complicate cross-study comparisons and restrict the reproducibility of large-scale microbiome research. ObjectiveThe Orion Microbiome Database was developed to overcome these challenges by providing a standardized, accessible, and reproducible resource for the integration and analysis of whole-genome shotgun (WGS) microbiome datasets. MethodsOrion aggregates raw metagenomic datasets from public repositories and harmonizes them into computed microbial profiles using automated and transparent analysis pipelines. Metadata are curated to ensure consistency and enable systematic cross-cohort comparisons. The platform provides interactive tools for data exploration, visualization, and downstream analysis, reducing redundancies in data preprocessing and lowering the barrier for both novice and expert users. Beyond research applications, Orion also serves as an educational resource, enabling microbiome data exploration in classroom settings. ConclusionBy unifying fragmented sequencing resources into a reproducible framework, Orion accelerates microbiome discovery, supports scalable cross-study investigations, and fosters integration of microbiome science into teaching and training. This database has the potential to serve as a model for future large-scale, community-driven platforms in microbiome research.

microbiology↗

A taxogenomics approach uncovers a new genus in the phylum Placozoa

The Placozoa [1] is a monotypic phylum of non-bilaterian marine animals. Its only species, Trichoplax adhaerens, was described in 1883 [2], Despite the worldwide distribution of placozoans [3-6], morphological differences are lacking among isolates from different geographic areas and, consequently, no other species in this phylum has been described and accepted for more than 130 years. However, recent single-gene studies on the genetic diversity of this \"species\" have revealed deeply divergent lineages of, as yet, undefined taxonomic ranks [3,5,6], Since single genes are not considered sufficient to define species [7], a whole nuclear genome comparison appears the most appropriate approach to determine relationships between placozoan lineages. Such a \"taxogenomics\" approach can help discover and diagnose potential additional species and, therefore, develop a much-needed, more robust, taxonomic framework for this phylum. To achieve this we sequenced the genome of a placozoan lineage isolated from Hong Kong (lineage H13), which is distantly related to T. adhaerens [6]. The 87 megabase genome assembly contains 12,010 genes. Comparison to the T. adhaerens genome [8] identified an average protein distance of 24.4% in more than 2,700 screened one-to-one orthologs, similar to levels observed between the chordate classes mammals and birds. Genome rearrangements are commonplace and >25% of genes are not collinear (i.e. they are not in the same order in the two genomes). Finally, a multi-gene distance comparison with other non-bilaterian phyla indicate genus level differences to T. adhaerens. These data highlight the large genomic diversity within the Placozoa and justifies the designation of lineage HI3 as a new species, Xxxxxxxxx yyyyyyyyyyyyy1 gen. et spaec. nov., now the second described placozoan species and the first in a new genus. Phylogenomic analyses furthermore supports a robust placement of the Placozoa as sister to a cnidarian-bilaterian clade.

evolutionary biology↗

Transcriptomic Resilience of a Coral Holobiont to Low pH

Ocean acidification is considered as one of the major threats for coral reefs at a global scale. Marine calcifying organisms, including stony corals, are expected to be the most affected by the predicted decrease of the surface water pH at the end of the century. The severity of the impacts on coral reefs remains as matter of controversy. Although previous studies have explored the physiological response of stony corals to changes in pH, the response of the holobiont (i.e. the coral itself plus its symbionts) remains largely unexplored. In the present study, we assessed the changes in overall gene expression of the coral Montipora digitata and its microalgal symbionts after a short (three days) and a longer (42 days) exposure to low pH (7.6). The short-term exposure to low pH caused small differences in the expression level of the host, impacting mostly genes associated with stress response in other scleractinians. Resilience to Acidification of a Coral Holobiont Longer exposure to low pH resulted in no significant changes in gene expression of the coral host. Gene expression in the eukaryotic symbionts remained unaltered at both exposure times. Our findings suggest resilience, in terms of gene expression, of the Montipora digitata holobiont to pH decrease, as well as capability to acclimatize to extended periods of exposure to low pH.

ecology↗