Project description:Metagenome data from soil samples were collected at 0 to 10cm deep from 2 avocado orchards in Channybearup, Western Australia, in 2024. Amplicon sequence variant (ASV) tables were constructed based on the DADA2 pipeline with default parameters.
Project description:Dietary intake of fruits and vegetables (FV) has been inversely associated with lower risk of ulcerative colitis. A pig model was used to evaluate the impact of feeding FV on the host response to dextran sulfate sodium (DSS)-induced colitis. Methods: Six-week-old pigs were fed a grower diet alone or supplemented with lyophilized FV equivalent to the half (half-FV) or full (full-FV) daily levels recommended for humans by the Dietary Guidelines for Americans (DGA). Pigs were fed a 1) grower diet alone (negative control), 2) grower diet and orally treated with 4% DSS for 10 days to induce colitis (positive control), 3) half-FV diet treated with 4% DSS or 4) full-FV diet treated with 4% DSS. Pigs were monitored for the development of clinical signs of colitis. Proximal colon (PC) contents and mucosa (PCM) were collected for gut metagenome, tissue transcriptome and histopathological analysis. Results: Pigs fed the full-FV diet did not exhibit diarrhea, showed less fecal occult blood (FOB), PCM crypt hyperplasia but with no differential expressed genes (DEG) or changes in PC microbiome diversity (p < 0.05). Pigs within the half-FV group exhibited increased group FOB and DEG associated with tissue remodeling, crypt and goblet cell hyperplasia in the PCM and no changes in PC microbiome diversity and two pigs exhibiting diarrhea (p < 0.05). Pigs within the DSS positive control group exhibited a reduced DEG involved with intestinal immune response and PC microbiome diversity with altered metagenome, increased group PCM erosion and FOB with persistent diarrhea in one pig (p < 0.05) Conclusions: Overall, our results showed that pigs fed a three-week full-FV supplemented diet, were resistant to DSS-induced colitis with a differential dose-dependent protective effect on host intestinal tissue and gut metagenome when exposed to an inflammatory challenge.
Project description:Virophages replicate within viral factories inside the Acanthamoeba cytoplasm, and decrease the infectivity and replication of their associated giant viruses. Culture isolation and metagenome analyses have suggested that they are common in our environment. By screening metagenomic databases in search of amoebal viruses, we detected virophage-related sequences among sequences generated from the same non-aerated bioreactor metagenome as recently screened by another team for virophage capsid-encoding genes. We describe here the assembled partial genome of a virophage closely related to Zamilon, which infects Acanthamoeba with mimiviruses of lineages B and C but not A. Searches for sequences related to amoebal giant viruses, other Megavirales representatives and virophages were conducted using BLAST against this bioreactor metagenome (PRJNA73603). Comparative genomic and phylogenetic analyses were performed using sequences from previously identified virophages. A total of 72 metagenome contigs generated from the bioreactor were identified as best matching with sequences from Megavirales representatives, mostly Pithovirus sibericum, pandoraviruses and amoebal mimiviruses from three lineages A-C, as well as from virophages. In addition, a partial genome from a Zamilon-like virophage, we named Zamilon 2, was assembled. This genome has a size of 6716 base pairs, corresponding to 39% of the Zamilon genome, and comprises partial or full-length homologs for 15 Zamilon predicted open reading frames (ORFs). Mean nucleotide and amino acid identities for these 15 Zamilon 2 ORFs with their Zamilon counterparts were 89% (range, 81-96%) and 91% (range, 78-99%), respectively. Notably, these ORFs included two encoding a capsid protein and a packaging ATPase. Comparative genomics and phylogenetic analyses indicated that the partial genome was that of a new Zamilon-like virophage. Further studies are needed to gain better knowledge of the tropism and prevalence of virophages in our biosphere and in humans.