Project description:Erythromycin (ERY) is a commonly used antibiotic that can be found in wastewater effluents globally. Due to the mechanisms by which they kill and prevent bacterial growth, antibiotics can have significant unwanted impacts on the fish gut microbiome. The overall objective of this project was to assess the effects of erythromycin and an antibiotic mixture on fish gut microbiomes. The project was split into two experiments to assess gut microbiome in response to exposure with ERY alone or in mixture with other common antibiotics. The objectives of experiment 1 were to understand uptake and depuration of ERY in juvenile rainbow trout (RBT) over a 7 d uptake followed by a 7 d depuration period using three concentrations of ERY. Furthermore, throughout the study changes in gut microbiome response were assessed. In experiment 2, a follow-up study was conducted using an identical experimental design to assess the impacts of an antibiotic-mixture (ERY, ampicillin, metronidazole, and ciprofloxacin at 100 µg/g each). Here, three matrices were analyzed, with gut collected for 16s metabarcoding, plasma for untargeted metabolomics, and brain for mRNA-seq analysis. ERY was depurated from the fish relatively quickly and gut microbiome dysbiosis was observed at 7 d after exposure, with a slight recovery after the 7 d depuration period. A greater number of plasma metabolites was dysregulated at 14 d compared to 7 d revealing temporality compared to gut microbiome dysbiosis. Furthermore, several transformation products of antibiotics and biomarker metabolites were observed in plasma due to antibiotic exposure. Brain transcriptome revealed only slight alterations due to antibiotic exposure. The results of these studies will help inform aquaculture practitioners and risk assessors when assessing the potential impacts of antibiotics in fish feed and the environment, with implications for host health.
Project description:The arsenal of genes that microbes express reflect the way in which they sense their environment. We have previously reported that the rumen microbiome composition and its coding capacity are different in animals having distinct feed efficiency states, even when fed an identical diet. Here, we reveal that many microbial populations show divergent proteome production in function of the feed efficiency state. Thus, proteomic data serve as a strong indicator of host feed efficiency state phenotype, overpowering predictions based on genomic and taxonomic information. We highlight protein production of specific phylogenies associated with each of the feed efficiency states. We also find remarkable plasticity of the proteome both in the individual population and at the community level, driven by niche partitioning and competition. These mechanisms result in protein production patterns which exhibit functional redundancy and checkerboard distribution that are tightly linked to the host feed efficiency phenotype. By linking microbial protein production and the ecological mechanisms that act within the microbiome feed efficiency states, our present work reveals a layer of complexity that bears immense importance to the current global of food security and sustainability.
Project description:We performed a deep, comparative metaproteomics study on three aerobic granular sludge wastewater treatment communities to determine the core microbiome and the occurrence and relative abundance of the central nutrient-removing organisms. Our systematic study underscores the importance of metaproteomics when characterizing complex microbiomes, and the necessity of accurate reference sequence databases to improve the comparison between studies and omics approaches.
Project description:Feed additives aiming to improve gastrointestinal health are frequently supplied to piglets after weaning but might be more effective when administered before weaning. In this period, feed additives can either be administered directly to neonates, or indirectly via sow’s feed. It is yet unknown what the effect of the administration route is on gut functionality and health. Therefore, we compared the effect of different dietary interventions on gut functionality after maternal administration (lactation feed) to the neonatal administration route (oral gavage). These feed interventions included medium chain fatty acids (MCFA), beta-glucans (BG), and galacto-oligosaccharides (GOS). We measured intestinal gene expression and microbiota composition after birth (d1) and after weaning (d31). Our results show that the type of intervention and the administration route influence gut functionality (microbiome and gene expression profiles). MCFA administration led to a more differentially orchestrated response when comparing the neonatal and maternal administration route then the other two additives, indicating the route of administration of the feed interventions is determinative for the outcome. This implies that for each nutritional intervention in early life of a pig the optimal route of administration needs to be determined.