ABSTRACT
Hundreds of microbiota genes are associated with host biology/disease. Unraveling the causal contribution of a microbiota gene to host biology remains difficult because many are encoded by nonmodel gut commensals and not genetically targetable. A general approach to identify their gene transfer methodology and build their gene manipulation tools would enable mechanistic dissections of their impact on host physiology. We developed a pipeline that identifies the gene transfer methods for multiple nonmodel microbes spanning five phyla, and we demonstrated the utility of their genetic tools by modulating microbiome-derived short-chain fatty acids and bile acids in vitro and in the host. In a proof-of-principle study, by deleting a commensal gene for bile acid synthesis in a complex microbiome, we discovered an intriguing role of this gene in regulating colon inflammation. This technology will enable genetically engineering the nonmodel gut microbiome and facilitate mechanistic dissection of microbiota-host interactions.
Subject(s)
Gastrointestinal Microbiome/genetics , Genes, Bacterial , Animals , Bile Acids and Salts/metabolism , CRISPR-Cas Systems/genetics , Clostridium/genetics , Colitis/chemically induced , Colitis/microbiology , Colitis/pathology , Dextran Sulfate , Drug Resistance, Microbial/genetics , Female , Gene Expression Regulation, Bacterial , Gene Transfer Techniques , Germ-Free Life , Inflammation/pathology , Intestines/pathology , Male , Metabolome/genetics , Metagenomics , Mice, Inbred C57BL , Mice, Knockout , Mutagenesis, Insertional/genetics , Mutation/genetics , RNA, Ribosomal, 16S/genetics , Transcription, GeneticABSTRACT
Aedes albopictus is a competent vector of numerous pathogens, representing a range of transmission cycles involving unique hosts. Despite the important status of this vector, variation in its feeding patterns is poorly understood. We examined the feeding patterns of Ae. albopictus utilizing resting collections in Long Island, NY, and contextualized blood meal sources with host availability measured by household interviews and camera traps. We identified 90 blood meals, including 29 humans, 22 cats, 16 horses, 12 opossums, 5 dogs, 2 goats, and 1 each of rabbit, rat, squirrel, and raccoon. This is only the third study of Ae. albopictus blood feeding biology that quantitatively assessed domestic host availability and is the first to do so with wild animals. Host feeding indices showed that cats and dogs were fed upon disproportionately often compared with humans. Forage ratios suggested a tendency to feed on cats and opossums and to avoid raccoons, squirrels, and birds. This feeding pattern was different from another published study from Baltimore, where Ae. albopictus fed more often on rats than humans. To understand whether these differences were because of host availability or mosquito population variation, we compared the fitness of New York and Baltimore Ae. albopictus after feeding on rat and human blood. In addition, we examined fitness within the New York population after feeding on human, rat, cat, horse, and opossum blood. Together, our results do not indicate major mosquito fitness differences by blood hosts, suggesting that fitness benefits do not drive Northeastern Ae. albopictus feeding patterns.
Subject(s)
Aedes/physiology , Host-Parasite Interactions , Mosquito Vectors/physiology , Animals , Cats , Dogs , Farms , Feeding Behavior , Female , Goats , Horses , Humans , New York , Opossums , Rabbits , Raccoons , Rats , Sciuridae , Suburban PopulationABSTRACT
BACKGROUND: Sugar feeding is an important behavior which may determine vector potential of female mosquitoes. Sugar meals can reduce blood feeding frequency, enhance survival, and decrease fecundity, as well as provide energetic reserves to fuel energy intensive behaviors such as mating and host seeking. Sugar feeding behavior can be harnessed for vector control (e.g. attractive toxic sugar baits). Few studies have addressed sugar feeding of Aedes albopictus, a vector of arboviruses of public health importance, including dengue and Zika viruses. To address this knowledge gap, we assessed sugar feeding patterns of Ae. albopictus for the first time in its invasive northeastern USA range. METHODOLOGY/PRINCIPAL FINDINGS: Using the cold anthrone fructose assay with robust sample sizes, we demonstrated that a large percentage of both male (49.6%) and female (41.8%) Ae. albopictus fed on plant or homopteran derived sugar sources within 24 hrs prior to capture. Our results suggest that sugar feeding behavior increases when environmental conditions are dry (high saturation deficit) and may vary by behavioral status (host seeking vs. resting). Furthermore, mosquitoes collected on properties with flowers (>3 blooms) had higher fructose concentrations compared to those collected from properties with few to no flowers (0-3). CONCLUSIONS/SIGNIFICANCE: Our results provide the first evidence of Ae. albopictus sugar feeding behavior in the Northeastern US and reveal relatively high rates of sugar feeding. These results suggest the potential success for regional deployment of toxic sugar baits. In addition, we demonstrate the impact of several environmental and mosquito parameters (saturation deficit, presence of flowers, host seeking status, and sex) on sugar feeding. Placing sugar feeding behavior in the context of these environmental and mosquito parameters provides further insight into spatiotemporal dynamics of feeding behavior for Ae. albopictus, and in turn, provides information for evidence-based control decisions.
