Faculty & Staff

  • Image of Kerri Coon

    Kerri Coon

    Assistant Professor of Bacteriology

    3552 Microbial Sciences Building
    Office: (608) 262-6919
    Lab: (608) 263-6375
    kerri.coon@wisc.edu

Start and Promotion Dates

  • Assistant Professor: 2019

Education

B.Sc. with Highest Distinction, Biology/Biostatistics, University of Virginia, 2011
Ph.D., Entomology, University of Georgia, 2017
Postdoctoral Research: University of Texas at Austin

Areas of Study

Ecology and Evolution of Host-Associated Microbes
Insect Microbiomes
Mosquito-Gut Microbiota Interactions
Vector-Borne Disease

Research Overview

Research in my lab centers on insect-microbe interactions, with a current focus on those between mosquitoes and their gut microbiota. We integrate field and lab-based experiments with bioinformatic approaches to tease apart the mechanisms by which microbes regulate fundamental processes in their mosquito hosts, from their development and reproduction to their ability to transmit disease-causing agents to humans and other mammals.

Other research topics of interest in my lab include: i) the ecology and evolution of host-associated microbial communities, ii) the interplay between resident and pathogenic microbes, and iii) the mechanisms underlying host-microbe specificity.

Teaching

Entomology 321: Physiology of Insects

MICROBIO 345: Introduction to Disease Biology

Lab Personnel

Picture of Arellano
Aldo Arellano
Grad Student
aaarellano2@wisc.edu
Picture of Diaz
Sebastian Diaz
Postdoc
diazzuleta@wisc.edu
Picture of Medina
Miguel Medina
Postdoc
medinamunoz@wisc.edu
Picture of Nichols
Holly Nichols
Grad Student
hlnichols@wisc.edu
Picture of Sommer
Andrew Sommer
Grad Student
asommer3@wisc.edu
Picture of Zhao
Serena Zhao
Grad Student
syzhao2@wisc.edu

Research Papers

  • Coon KL, Hegde S, Hughes GL (2022) Interspecies microbiome transplantation recapitulates microbial acquisition in mosquitoes. Microbiome 10((1)):58 PMC8996512 · Pubmed · DOI

    Mosquitoes harbor microbial communities that play important roles in their growth, survival, reproduction, and ability to transmit human pathogens. Microbiome transplantation approaches are often used to study host-microbe interactions and identify microbial taxa and assemblages associated with health or disease. However, no such approaches have been developed to manipulate the microbiota of mosquitoes.

  • Arellano AA, Coon KL (2022) Bacterial communities in carnivorous pitcher plants colonize and persist in inquiline mosquitoes. Animal microbiome 4((1)):13 PMC8848819 · Pubmed · DOI

    The leaves of carnivorous pitcher plants harbor diverse communities of inquiline species, including bacteria and larvae of the pitcher plant mosquito (Wyeomyia smithii), which aid the plant by processing captured prey. Despite the growing appreciation for this microecosystem as a tractable model in which to study food web dynamics and the moniker of W. smithii as a 'keystone predator', very little is known about microbiota acquisition and assembly in W. smithii mosquitoes or the impacts of W. smithii-microbiota interactions on mosquito and/or plant fitness.

  • Tawidian P, Coon KL, Jumpponen A, Cohnstaedt LW, Michel K (2021) Host-Environment Interplay Shapes Fungal Diversity in Mosquitoes. mSphere 6((5)):e0064621 PMC8550294 · Pubmed · DOI

    Mosquito larvae encounter diverse assemblages of bacteria (i.e., "microbiota") and fungi in the aquatic environments that they develop in. However, while a number of studies have addressed the diversity and function of microbiota in mosquito life history, relatively little is known about mosquito-fungus interactions outside several key fungal entomopathogens. In this study, we used high-throughput sequencing of internal transcribed spacer 2 (ITS2) metabarcode markers to provide the first simultaneous characterization of the fungal communities in field-collected Aedes albopictus larvae and their associated aquatic environments. Our results reveal unprecedented variation in fungal communities among adjacent but discrete larval breeding habitats. Our results also reveal a distinct fungal community assembly in the mosquito gut versus other tissues, with gut-associated fungal communities being most similar to those present in the environment where larvae feed. Altogether, our results identify the environment as the dominant factor shaping the fungal community associated with mosquito larvae, with no evidence of environmental filtering by the gut. These results also identify mosquito feeding behavior and fungal mode of nutrition as potential drivers of tissue-specific fungal community assembly after environmental acquisition. IMPORTANCE The Asian tiger mosquito, Aedes albopictus, is the dominant mosquito species in the United States and an important vector of arboviruses of major public health concern. One aspect of mosquito control to curb mosquito-borne diseases has been the use of biological control agents such as fungal entomopathogens. Recent studies also demonstrate the impact of mosquito-associated microbial communities on various mosquito traits, including vector competence. However, while much research attention has been dedicated to understanding the diversity and function of mosquito-associated bacterial communities, relatively little is known about mosquito-associated fungal communities. A better understanding of the factors that drive fungal community diversity and assembly in mosquitoes will be essential for future efforts to target mosquito-associated bacteria and fungi for mosquito and mosquito-borne disease control.

  • Cansado-Utrilla C, Zhao SY, McCall PJ, Coon KL, Hughes GL (2021) The microbiome and mosquito vectorial capacity: rich potential for discovery and translation. Microbiome 9((1)):111 PMC8132434 · Pubmed · DOI

    Microbiome research has gained considerable interest due to the emerging evidence of its impact on human and animal health. As in other animals, the gut-associated microbiota of mosquitoes affect host fitness and other phenotypes. It is now well established that microbes can alter pathogen transmission in mosquitoes, either positively or negatively, and avenues are being explored to exploit microbes for vector control. However, less attention has been paid to how microbiota affect phenotypes that impact vectorial capacity. Several mosquito and pathogen components, such as vector density, biting rate, survival, vector competence, and the pathogen extrinsic incubation period all influence pathogen transmission. Recent studies also indicate that mosquito gut-associated microbes can impact each of these components, and therefore ultimately modulate vectorial capacity. Promisingly, this expands the options available to exploit microbes for vector control by also targeting parameters that affect vectorial capacity. However, there are still many knowledge gaps regarding  mosquito-microbe interactions  that need to be addressed in order to exploit them efficiently. Here, we review current evidence of impacts of the microbiome on aspects of vectorial capacity, and we highlight likely opportunities for novel vector control strategies and areas where further studies are required. Video abstract.

  • Coon KL, Valzania L, Brown MR, Strand MR (2020) Predaceous Toxorhynchites mosquitoes require a living gut microbiota to develop. Proceedings. Biological sciences 287((1919)):20192705 PMC7015322 · Pubmed · DOI

    Most species of mosquitoes are detritivores that feed on decaying plant and animal materials in their aquatic environment. Studies of several detritivorous mosquito species indicate that they host relatively low diversity communities of microbes that are acquired from the environment while feeding. Our recent results also indicate that detritivorous species normally require a living gut microbiota to grow beyond the first instar. Less well known is that some mosquitoes, including those belonging to the genus Toxorhynchites , are predators that feed on other species of mosquitoes and nektonic prey. In this study, we asked whether predaceous Toxorhynchites amboinensis larvae still require living microbes in their gut in order to develop. Using the detritivorous mosquito Aedes aegypti as prey, we found that T. amboinensis larvae harbour bacterial communities that are highly similar to that of their prey. Functional assays showed that T. amboinensis first instars provided axenic (i.e. bacteria-free) prey failed to develop, while two bacterial species present in gnotobiotic (i.e. colonized by one or more known bacterial species) prey successfully colonized the T. amboinensis gut and rescued development. Axenic T. amboinensis larvae also displayed defects in growth consistent with previously identified roles for microbe-mediated gut hypoxia in nutrient acquisition and assimilation in A. aegypti. Collectively, these results support a conserved role for gut microbes in regulating the development of mosquitoes with different feeding strategies.

  • Raymann K, Coon KL, Shaffer Z, Salisbury S, Moran NA (2018) Pathogenicity of Serratia marcescens Strains in Honey Bees. mBio 9((5)): PMC6178626 · Pubmed · DOI

    No abstract available.

  • Valzania L, Martinson VG, Harrison RE, Boyd BM, Coon KL, Brown MR, Strand MR (2018) Both living bacteria and eukaryotes in the mosquito gut promote growth of larvae. PLoS neglected tropical diseases 12((7)):e0006638 PMC6057668 · Pubmed · DOI

    No abstract available.

  • Valzania L, Coon KL, Vogel KJ, Brown MR, Strand MR (2018) Hypoxia-induced transcription factor signaling is essential for larval growth of the mosquito Aedes aegypti . Proceedings of the National Academy of Sciences of the United States of America 115((3)):457-465 PMC5777003 · Pubmed · DOI

    No abstract available.

  • Coon KL, Valzania L, McKinney DA, Vogel KJ, Brown MR, Strand MR (2017) Bacteria-mediated hypoxia functions as a signal for mosquito development. Proceedings of the National Academy of Sciences of the United States of America 114((27)):E5362-E5369 PMC5502624 · Pubmed · DOI

    No abstract available.

  • Vogel KJ, Valzania L, Coon KL, Brown MR, Strand MR (2017) Transcriptome Sequencing Reveals Large-Scale Changes in Axenic Aedes aegypti Larvae. PLoS neglected tropical diseases 11((1)):e0005273 PMC5245907 · Pubmed · DOI

    No abstract available.

  • Coon KL, Brown MR, Strand MR (2016) Mosquitoes host communities of bacteria that are essential for development but vary greatly between local habitats. Molecular ecology 25((22)):5806-5826 PMC5118126 · Pubmed · DOI

    Mosquitoes are insects of interest because several species vector disease-causing pathogens to humans and other vertebrates. We previously reported that mosquitoes from long-term laboratory cultures require living bacteria in their gut to develop, but development does not depend on particular species of bacteria. Here, we focused on three distinct but interrelated areas of study to better understand the role of bacteria in mosquito development by studying field and laboratory populations of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus from the southeastern United States. Sequence analysis of bacterial 16S rRNA gene amplicons showed that bacterial community composition differed substantially in larvae from different collection sites, whereas larvae from the same site shared similarities. Although previously unknown to be infected by Wolbachia, results also indicated that Ae. aegypti from one field site hosted a dual infection. Regardless of collection site or factors like Wolbachia infection, however, each mosquito species required living bacteria in their digestive tract to develop. Results also identified several concerns in using antibiotics to eliminate the bacterial community in larvae in order to study its developmental consequences. Altogether, our results indicate that several mosquito species require living bacteria for development. We also hypothesize these species do not rely on particular bacteria because larvae do not reliably encounter the same bacteria in the aquatic habitats they develop in.

  • Coon KL, Brown MR, Strand MR (2016) Gut bacteria differentially affect egg production in the anautogenous mosquito Aedes aegypti and facultatively autogenous mosquito Aedes atropalpus (Diptera: Culicidae). Parasites & vectors 9((1)):375 PMC4929711 · Pubmed · DOI

    Aedes aegypti and A. atropalpus are related mosquitoes that differ reproductively. Aedes aegypti must blood-feed to produce eggs (anautogenous) while A. atropalpus always produces a first clutch of eggs without blood-feeding (facultatively autogenous). We recently characterized the gut microbiota of A. aegypti and A. atropalpus that were reared identically in the laboratory. Here, we assessed the effects of specific members of the gut microbiota in A. aegypti and A. atropalpus on female fitness including egg production.

  • Coon KL, Vogel KJ, Brown MR, Strand MR (2014) Mosquitoes rely on their gut microbiota for development. Molecular ecology 23((11)):2727-39 PMC4083365 · Pubmed · DOI

    Field studies indicate adult mosquitoes (Culicidae) host low diversity communities of bacteria that vary greatly among individuals and species. In contrast, it remains unclear how adult mosquitoes acquire their microbiome, what influences community structure, and whether the microbiome is important for survival. Here, we used pyrosequencing of 16S rRNA to characterize the bacterial communities of three mosquito species reared under identical conditions. Two of these species, Aedes aegypti and Anopheles gambiae, are anautogenous and must blood-feed to produce eggs, while one, Georgecraigius atropalpus, is autogenous and produces eggs without blood feeding. Each mosquito species contained a low diversity community comprised primarily of aerobic bacteria acquired from the aquatic habitat in which larvae developed. Our results suggested that the communities in Ae. aegypti and An. gambiae larvae share more similarities with one another than with G. atropalpus. Studies with Ae. aegypti also strongly suggested that adults transstadially acquired several members of the larval bacterial community, but only four genera of bacteria present in blood fed females were detected on eggs. Functional assays showed that axenic larvae of each species failed to develop beyond the first instar. Experiments with Ae. aegypti indicated several members of the microbial community and Escherichia coli successfully colonized axenic larvae and rescued development. Overall, our results provide new insights about the acquisition and structure of bacterial communities in mosquitoes. They also indicate that three mosquito species spanning the breadth of the Culicidae depend on their gut microbiome for development.