TY - JOUR
T1 - Chromobacterium Biopesticide Exposure Does Not Select for Resistance in Aedes Mosquitoes
AU - Engdahl, Cecilia Springer
AU - Caragata, Eric P.
AU - Tavadia, Mihra
AU - Dimopoulos, George
N1 - Funding Information:
This work was supported by National Institutes of Health NIAID grant R21AI146398 and by the Bloomberg Philanthropies. C.S.E. was supported by the Swedish Research Council grant nr 2018-00334. E.P.C.’s research is supported by the U.S. Department of Agriculture National Institute of Food and Agriculture, Hatch project 1026692.
Funding Information:
We thank the Johns Hopkins Malaria Research Institute Insectary core facility, Shengzhang Dong for helpful discussion about the infection and RNA-Seq assays, and Deborah McClelland for editorial assistance. This work was supported by National Institutes of Health NIAID grant R21AI146398 and by the Bloomberg Philanthropies. C.S.E. was supported by the Swedish Research Council grant nr 2018-00334. E.P.C.’s research is supported by the U.S. Department of Agriculture National Institute of Food and Agriculture, Hatch project 1026692. Conceptualization, C.S.E., E.P.C., G.D.; Methodology, C.S.E., E.P.C., G.D.; Investigation, C.S.E., E.P.C., M.T.; Visualization, C.S.E., E.P.C.; Supervision, G.D.; Writing—original draft, C.S.E., E.P.C.; Writing—review & editing, C.S.E., E.P.C., G.D. G.D. and E.P.C. are authors on a patent describing the Csp_P biopesticide formulation (P16318). We declare no other conflict of interest.
Publisher Copyright:
Copyright © 2023 Engdahl et al.
PY - 2023/3
Y1 - 2023/3
N2 - Developing effective tools to control mosquito populations is essential for reducing the incidence of diseases like malaria and dengue. Biopesticides of microbial origin are a rich, underexplored source of mosquitocidal compounds. We previously developed a biopesticide from the bacterium Chromobacterium sp. Panama that rapidly kills vector mosquito larvae, including Aedes aegypti and Anopheles gambiae. Here, we demonstrate that two independent Ae. aegypti colonies exposed to a sublethal dose of that biopesticide over consecutive generations persistently exhibited high mortality and developmental delays, indicating that resistance did not develop during the study period. Critically, the descendants of biopesticide-exposed mosquitoes experienced decreased longevity and did not display increased susceptibility to dengue virus or decreased susceptibility to common chemical insecticides. Through RNA sequencing, we observed no link between biopesticide exposure and the increased activity of xenobiotic metabolism and detoxification genes typically associated with insecticide resistance. These findings indicate that the Chromobacterium biopesticide is an exciting, emerging mosquito control tool. IMPORTANCE Vector control is an essential part of mitigating diseases caused by pathogens that mosquitoes spread. Modern vector control is highly reliant on using synthetic insecticides to eliminate mosquito populations before they can cause disease. However, many of these populations have become resistant to commonly used insecticides. There is a strong need to explore alternative vector control strategies that aim to mitigate disease burden. Biopesticides, insecticides of biological origin, can have unique mosquitocidal activities, meaning they can effectively kill mosquitoes that are already resistant to other insecticides. We previously developed a highly effective mosquito biopesticide from the bacterium Chromobacterium sp. Csp_P. Here, we investigate whether exposure to a sublethal dose of this Csp_P biopesticide over 9 to 10 generations causes resistance to arise in Aedes aegypti mosquitoes. We find no evidence of resistance at the physiological or molecular levels, confirming that the Csp_P biopesticide is a highly promising new tool for controlling mosquito populations.
AB - Developing effective tools to control mosquito populations is essential for reducing the incidence of diseases like malaria and dengue. Biopesticides of microbial origin are a rich, underexplored source of mosquitocidal compounds. We previously developed a biopesticide from the bacterium Chromobacterium sp. Panama that rapidly kills vector mosquito larvae, including Aedes aegypti and Anopheles gambiae. Here, we demonstrate that two independent Ae. aegypti colonies exposed to a sublethal dose of that biopesticide over consecutive generations persistently exhibited high mortality and developmental delays, indicating that resistance did not develop during the study period. Critically, the descendants of biopesticide-exposed mosquitoes experienced decreased longevity and did not display increased susceptibility to dengue virus or decreased susceptibility to common chemical insecticides. Through RNA sequencing, we observed no link between biopesticide exposure and the increased activity of xenobiotic metabolism and detoxification genes typically associated with insecticide resistance. These findings indicate that the Chromobacterium biopesticide is an exciting, emerging mosquito control tool. IMPORTANCE Vector control is an essential part of mitigating diseases caused by pathogens that mosquitoes spread. Modern vector control is highly reliant on using synthetic insecticides to eliminate mosquito populations before they can cause disease. However, many of these populations have become resistant to commonly used insecticides. There is a strong need to explore alternative vector control strategies that aim to mitigate disease burden. Biopesticides, insecticides of biological origin, can have unique mosquitocidal activities, meaning they can effectively kill mosquitoes that are already resistant to other insecticides. We previously developed a highly effective mosquito biopesticide from the bacterium Chromobacterium sp. Csp_P. Here, we investigate whether exposure to a sublethal dose of this Csp_P biopesticide over 9 to 10 generations causes resistance to arise in Aedes aegypti mosquitoes. We find no evidence of resistance at the physiological or molecular levels, confirming that the Csp_P biopesticide is a highly promising new tool for controlling mosquito populations.
KW - Aedes aegypti
KW - Chromobacterium Csp_P
KW - RNA-Seq
KW - biopesticide
KW - dengue
KW - fitness
KW - insecticide resistance
KW - mosquito
KW - selection
UR - http://www.scopus.com/inward/record.url?scp=85153898605&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85153898605&partnerID=8YFLogxK
U2 - 10.1128/mbio.00480-23
DO - 10.1128/mbio.00480-23
M3 - Article
C2 - 37017525
AN - SCOPUS:85153898605
SN - 2161-2129
VL - 14
JO - mBio
JF - mBio
IS - 2
ER -