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Biology subjects

Willing, B. P.

Publications and source records attributed to Willing, B. P..

9 recordsLinked to original sources

Mapping Glycan Binding Profiles of the Gut Bacteria using Liquid Glycan Array (LiGA)

Glycan-microbe interactions are central to gut colonization and host-microbiota communication. Here, we apply a DNA-encoded Liquid Glycan Array (LiGA) to quantify interactions between live gut bacteria and multivalent natural or mirror glycans. LiGA comprises glycosylated M13 bacteriophage bearing silent DNA barcodes that encode glycan identity and density. Using LiGA, we profiled glycan binding across 16 Limosilactobacillus reuteri strains isolated from murine, porcine, poultry, and human hosts, and then extended the approach to profile glycan binding of taxonomically diverse bacteria from three phyla Bacillota, Bacteroidota, Pseudomonadota consisting of nine different species. Recent discussion of mirror-image microorganisms raise a question whether these microorganisms could interact with present-day life by engaging naturally chiral glycans. We demonstrated that this question can be assessed by testing the binding of mirror-image glycans to natural bacteria. Evaluation of enantiomers of common glycan revealed cross-chiral recognition by Escherichia coli and L. reuteri, indicating that these bacteria can used mirror-image glycans to engage for adhesion and potential colonization. By symmetry the same arguments extends to mirror microorganisms and glycans of naturally chirality. We established that LiGA enables efficient characterization of bacterial glycan binding and provides new insights into intestinal microbial ecology.

biochemistry↗

The impact of wild-boar derived microbiota transplantation on piglet microbiota, metabolite profile and gut proinflammatory cytokine production differs from sow-derived microbiota

Colonization of co-evolved, species-specific microbes in early life plays a crucial role in gastrointestinal development and immune function. This study hypothesized modern pig production practices have resulted in the loss of co-evolved species and critical symbiotic host- microbe interactions. To test this, we reintroduced microbes from wild boars (WB) into conventional piglets to explore their colonization dynamics and effects on gut microbial communities, metabolite profiles, and immune responses. At postnatal day (PND) 21, 48 piglets were assigned to four treatment groups: 1) WB-derived mixed microbial community (MMC), 2) sow-derived MMC, 3) a combination of WB and sow MMC (Mix), or 4) Control (PBS). Post- transplantation analyses at PND 48 revealed distinct microbial communities in WB-inoculated piglets compared to Controls, with trends toward differentiation from Sow but not Mix groups. WB-derived microbes were more successful in colonizing piglets, particularly in the Mix group, where they competed with sow-derived microbes. WB group cecal digesta enriched with Lactobacillus helveticus, Lactobacillus mucosae, and Lactobacillus pontis. Cecal metabolite analysis showed that WB piglets were enriched in histamine, acetyl-ornithine, ornithine, citrulline, and other metabolites, with higher histamine levels linked to Lactobacillus abundance. WB piglets exhibited lower cecal IL-1{beta} and IL-6 levels compared to Controls and Sow groups, while the Mix group showed reduced IFN-{gamma}, IL-2, and IL-6 compared to the Sow group. No differences in weight gain, fecal scores, or plasma cytokines were observed, indicating no adverse effects. These findings support that missing WB microbes effectively colonize domestic piglets and may positively impact metabolite production and immune responses. ImportanceThis study addresses the growing concern over losing co-evolved, species-specific microbes in modern agricultural practices, particularly in pig production. The implementation of strict biosecurity measures and widespread antibiotic use in conventional farming systems may disrupt crucial host-microbe interactions that are essential for gastrointestinal development and immune function. Our research demonstrates that by reintroducing wild boar-derived microbes into domestic piglets, these co-evolved microbes can successfully colonize the gut, influence microbial community composition, and alter metabolite profiles and immune responses without causing adverse effects. These findings also suggest that these co-evolved microbes can fill an intestinal niche, positively impacting immune activation. This research lays the groundwork for future strategies to enhance livestock health and performance by restoring natural microbial populations that produce immune-modulating metabolites. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=156 SRC="FIGDIR/small/623678v1_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@6ec5c2org.highwire.dtl.DTLVardef@79804corg.highwire.dtl.DTLVardef@d63016org.highwire.dtl.DTLVardef@1ef0010_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Metabolic modeling of microbial communities in the chicken ceca reveals a landscape of competition and co-operation

With their ability to degrade dietary fibers to liberate otherwise unavailable substrates, members of the Bacteroidales exert a substantial influence on the microbiome of the lower intestine. Currently our knowledge of how this influence translates to the metabolic interactions that support community structure is limited. Here we applied constraints-based modeling to chicken cecal communities to investigate metabolic interactions in the presence and absence of Bacteroides. From metagenomic datasets previously generated from 33 chicken ceca, we constructed 237 metagenome-assembled genomes. Metabolic modeling of communities built from these genomes generated profiles of short chain fatty acids largely consistent with experimental assays and confirmed the role of B. fragilis as a metabolic hub, central to the production of metabolites consumed by other taxa. In its absence, communities undergo significant functional reconfiguration, with metabolic roles typically fulfilled by B. fragilis assumed by multiple taxa. Beyond B. fragilis, we found Escherichia coli and Lactobacillus crispatus also mediate influential metabolic roles that vary in the presence or absence of B. fragilis. Compensatory adaptations adopted by the microbiome in the absence of B. fragilis resulted in metabolic profiles previously associated with inflammatory bowel disease in humans, including energy deficiency, increased lactate production and altered amino acid metabolism. This work demonstrates the potential of chicken cecal microbiomes to investigate the complex metabolic interactions and key contributions that drive community dynamics.

systems biology↗

Maternal humoral factors modulate offspring gut immune homeostasis to mitigate diabetes development

Environmental risk factors possess the potential to modulate the pathogenesis of type I diabetes (T1D). Foremost among these factors are early life influences impacting the gastrointestinal (GI) tract. During infancy, both the microbiota and immune system are influenced by maternal factors contributing to key events in the neonatal GI tract. Despite the well-known importance of maternal factors on infant immune development, whether maternal immune dysregulation and dysbiosis can perpetuate the same in offspring remains largely unknown. To explore how these maternal factors impact offspring disease development, we used IgA-deficiency induced maternal dysbiosis in Non-Obese Diabetic (NOD) dams to study T1D development in their progeny. We found that maternal dysbiosis and absence of IgA led to changes in IgA-sufficient offspring immune development resulting in heightened GI immune activity. Maternal dysbiosis also contributed to altered microbiome establishment in progeny, such that pups exhibited reduced colonic abundance of Akkermansia muciniphila and Clostridoides difficile. In adulthood, these mice exhibited a lowered incidence of T1D. This protection was replicated by fostering high incidence offspring to dysbiotic dams, prompting us to propose that altered breast milk composition in dysbiotic dams can influence immune development and microbiome establishment in offspring, contributing to T1D resistance.

immunology↗

Impact of a defined bacterial community including and excluding Megamonas hypermegale on broiler cecal microbiota and resistance to Salmonella infection

Intensive broiler production practices impair the transmission of commensal microbes from hens to offspring, resulting in a lower abundance of non-spore-forming strict anaerobic bacteria. We evaluated the effects of colonization by a defined community (DC) of bacteria including and excluding Megamonas hypermegale in chicks challenged with Salmonella. Inoculation with DC resulted in higher phylogenetic diversity and the dominance of Bacteroidetes species in the cecal microbiota, with a decrease in the relative abundance of Salmonella and Escherichia/Shigella, as well as a lower Enterobacteriaceae load. Substantial shifts in microbiota composition were coupled with subtle changes in metabolites and host responses, including changes in interferon-{gamma}, macrophage colony-stimulating factor, propionate, valerate, and isovalerate concentrations in the ceca. We identified bacterial species that were able to establish and persist after a single exposure, many of which were members of Bacteroidetes. Although co-culture with M. hypermegale reduced Salmonella counts by 99.3% in vitro, in vivo inoculation of M. hypermegale increased splenic Salmonella counts in inoculated chicks. The use of DC containing bacteria isolates harvested from the cecal contents of mature chickens can recapitulate the changes in volatile fatty acid concentrations observed in birds colonized with complex communities, and the presence of M. hypermegale specifically enhances the production of propionate. Our findings suggest that the use of DC can be explored as a strategy to control disease occurrence in broiler production; however, further research is warranted to properly understand the role of individual species in the broiler cecal community aiding the formulation of appropriate DCs. ImportanceIntensive production practices can reduce beneficial gut bacteria in broiler chickens, potentially leading to higher disease risk. We investigated whether introducing a defined community (DC) of beneficial bacteria, along with M. hypermegale, could improve gut health and resistance to Salmonella in broiler chicks. Our findings show that DC increases microbial diversity and reduces the relative abundance of potential pathogens, like Salmonella and Escherichia/Shigella, which was coupled with subtle changes in the immune responses of the birds and higher concentration of volatile fatty acids in the ceca. This study suggests that using DC can enhance poultry health and reduce disease, providing a potential strategy to improve broiler production. However, further research is needed to understand the roles of individual bacteria and refine these bacterial communities for practical use in farming. This work holds promise for developing natural methods to enhance poultry health and safety.

microbiology↗

Chicken cecal microbial functional capacity and resistome differ by age and barn disinfection practice

Chemical disinfectants and water-wash methods are widely employed in sanitizing broiler chicken barns. Previous studies showed that chemical disinfectants affect environmental microbial composition and antibiotic resistance genes (ARGs). However, little is known regarding how barn disinfection treatments impact the chicken gut resistome and microbial functionality. The current study compared the effects of chemical disinfection and water-wash method on the gut microbiome and resistome of commercial broilers using a crossover experimental design after 2 production cycles at 7 barns. Shotgun metagenomic sequencing performed on cecal contents collected at day 7 and 30 also allowed evaluation of age-associated characteristics of microbiome. Age of the chickens had the largest effects on the resistome, with younger birds having increased relative abundance of total ARGs (P<0.05) and differences in resistance mechanism, however, functional and resistome differences were also identified by barn sanitation practice. At day 7, chickens in chemically-disinfected barns had decreased functional capacity related to amino acid synthesis compared to the water-wash group. Additionally, genes related to stringent response were enriched in chickens raised under chemically-disinfected condition (FDR-P<0.05), suggesting selection for stress resistance. Consistently, lower abundance of genetic pathways encoding amino acid biosynthesis associated with cecal Helicobacter pullorum was observed in the disinfection group at day 30 compared to the water-wash group, with the same pattern in short-chain fatty acid biosynthesis (FDR-P<0.05). Overall, while the use of disinfectants in barn sanitation slightly affected the relative abundance of some ARGs in the gut, age had a dominant effect on the microbial functionality and resistome. ImportanceThis is the first study to evaluate the effect of sanitation practices on microbial functional capacity and resistome of chickens in a commercial setting. It is also amongst the biggest metagenomics studies on the gut microbiome of broiler chickens. It provides new insights into the changes in resistance profiles with age that agree with other studies examining maturation of the microbiome in other species. Finally, the current study provides valuable insights for informing industry sanitation practices and future studies on broiler gut microbiome and resistome.

microbiology↗

A comparison of wild boar and domestic pig microbiota does not reveal a loss of microbial species but an increase in alpha diversity and opportunistic genera in domestic pigs

The microbiome of wild animals is believed to be co-evolved with host species, which may play an important role in host physiology. It has been hypothesized that the rigorous hygienic practice in combination with antibiotics and diets with simplified formulas used in the modern swine industry may negatively affect the establishment and development of the gut microbiome. In this study, we evaluated the fecal microbiome of 90 domestic pigs sampled from 9 farms in Canada and 39 wild pigs sampled from three different locations on two continents (North America and Europe) using 16S rRNA gene amplicon sequencing. Surprisingly, the gut microbiome in domestic pigs exhibited higher alpha-diversity indices than wild pigs (P<0.0001). The wild pig microbiome showed a lower Firmicutes to Bacteroidetes ratio and a higher presence of bacterial phyla Elusimicrobiota, Verrucomicrobiota, Cyanobacteria, and Fibrobacterota compared to their domestic counterparts. At the genus level, wild pig microbiome had enriched genera that were known for fibre degradation and short-chained fatty acids production. Interestingly, the phylum Fusobacteriota was only observed in domestic pigs. We identified 31 ASVs that were commonly found in the pig gut microbiome regardless of host sources, which could be recognized as members of the core gut microbiome. Interestingly, we found a few ASVs missing in domestic pigs that were prevalent in wild ones, whereas domestic pigs harbored 59 ASVs that were completely absent in wild pigs. The present study sheds light on the impact of domestication on the pig gut microbiome, including the gain of new genera. ImportanceThe microbiome of pigs plays a crucial role in shaping host physiology and health. This study looked to identify if domestication and current rearing practices have resulted in a loss of co-evolved bacterial species by comparing the microbiome of wild boar and conventionally raised pigs. It represents a comparison of domestic and wild pigs with the largest sample sizes, and is the first to examine wild boars from multiple sites and continents. We were able to identify core microbiome members that were shared between wild and domestic populations, and counter to expectation, few microbes were identified to be lost from wild boar. Nevertheless, the microbiome of wild boars was distinct from domestic pigs, with notably lower abundance of important pathogenic genera. The differences in microbial composition may identify an opportunity to shift the microbial community of domestic pigs towards that of wild boar with the intent to reduce pathogen load.

microbiology↗

Isolation and characterization of a novel temperate Escherichia coli bacteriophage, Kapi1, which modifies the O-antigen and contributes to the competitiveness of its host during colonization of the murine gastrointestinal tract.

In this study, we describe the isolation and characterization of novel bacteriophage vB_EcoP_Kapi1 (Kapi1) isolated from a strain of commensal Escherichia coli inhabiting the gastrointestinal tract of healthy mice. We show that Kapi1 is a temperate phage integrated into tRNA argW of strain MP1 and describe its genome annotation and structure. Kapi1 shows limited homology to other characterized prophages but is most similar to the seroconverting phages of Shigella flexneri, and clusters taxonomically with P22-like phages. The receptor for Kapi1 is the lipopolysaccharide O-antigen, and we further show that Kapi1 alters the structure of its hosts O-antigen in multiple ways. Kapi1 displays unstable lysogeny, and we find that lysogeny is favored during growth in simulated intestinal fluid. Furthermore, Kapi1 lysogens have a competitive advantage over their non-lysogenic counterparts both in vitro and in vivo, suggesting a role for Kapi1 during colonization. We thus report the use of MP1 and Kapi1 as a model system to explore the molecular mechanisms of mammalian colonization by E. coli to ask what the role(s) of prophages in this context might be. ImportanceAlthough research exploring the microbiome has exploded in recent years, our understanding of the viral component of the microbiome is lagging far behind our understanding of the bacterial component. The vast majority of intestinal bacteria carry prophages integrated into their chromosomes, but most of these bacteriophages remain uncharacterized and unexplored. Here, we isolate and characterize a novel temperate bacteriophage infecting a commensal strain of Escherichia coli. We aim to explore the interactions between bacteriophages and their hosts in the context of the gastrointestinal tract, asking what role(s) temperate bacteriophage may play in growth and survival of bacteria in the gut. Understanding the fundamental biology of gut commensal bacteria can inform the development of novel antimicrobial or probiotic strategies for intestinal infections.

microbiology↗

The use of disinfectant in barn cleaning alters microbial composition and increases carriage of Campylobacter jejuni in broiler chickens

To maintain food safety and flock health in broiler chicken production, biosecurity approaches to keep chicken barns free of pathogens are important. Canadian broiler chicken producers must deep clean their barns with chemical disinfectants at least once annually (full disinfection; FD) and may wash with water (water-wash; WW) throughout the year. However, many producers use FD after each flock, assuming a greater efficacy of more stringent cleaning protocols, although little information is known regarding how these two cleaning practices affect pathogen population and gut microbiota. In the current study, a cross-over experiment over four production cycles was conducted in seven commercial chicken barns to compare WW and FD. We evaluated the effects of barn cleaning method on the commercial broiler performance, cecal microbiota composition, pathogen occurrence and abundance, as well as short-chain fatty acid concentrations in the month-old broiler gut. The 30-day body weight and mortality rate were not affected by the barn cleaning methods. The WW resulted in a modest but significant effect on the structure of broiler cecal microbiota (weighted-UniFrac; adonis p = 0.05, and unweighted-UniFrac; adonis p = 0.01), with notable reductions in Campylobacter jejuni occurrence and abundance. In addition, the WW group had increased cecal acetate, butyrate and total short-chain fatty acid concentrations, which were negatively correlated with C. jejuni abundance. Our results support the use of WW over FD to enhance the activity of the gut microbiota and potentially reduce zoonotic transmission of C. jejuni in broiler production without previous disease challenges.

microbiology↗