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Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS) to understand chemical susceptibility across bee species.
Citation:
Blatz, D. AND C. LaLone. Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS) to understand chemical susceptibility across bee species. Bayer Meeting, Duluth, MN, January 07, 2021. https://doi.org/10.23645/epacomptox.13516757
Impact/Purpose:
Standard Crops that serve as our food sources require both protection from pest insects and disease. Common farming practices incorporate the use of chemicals, to some extent, to maximize yield and quality of such crops. Pollinators, such as bees, are critical to farming food crops as they fertilize the plants so they can be fruitful. There is a gentle balance in both applying chemicals to crops to protect them and reducing the likelihood that the pollinators are exposed to levels of the chemicals that could cause them harm and therefore impact their role in agriculture. The best way to prevent unintended consequences of chemicals in farming is to have a clear understanding of the potential for exposure to those chemicals in the environment and information on the doses of the chemical that could cause harm to the variety of pollinator species. Unfortunately, there typically may not be enough data to adequately understand the potential for these chemicals to harm unintended organism. Therefore, the US EPA has developed a computer tool called Sequence Alignment to Predict Across Species Sensitivity tool (SeqAPASS) that allows us to gain an initial understanding of whether a bee species may or may not be susceptible to a particular chemical. This information, that can be generated rapidly, can assist in informing what studies are needed on which species that would help us understand if the chemical would harm an unintended species. Procedure for testing every feature/function/dataset produced by the Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS) tool in a step by step manner. The SeqAPASS tool allows users to compare protein similarity across species. This is important because chemicals act on protein targets. Therefore, by understanding how similar proteins are across species, the SeqAPASS tool can produce chemical susceptibility predictions across hundreds of species rapidly.
Description:
As pollinators of numerous crops, bees are critical to global agriculture. Therefore, it is important to protect the health of these insects to ensure chemicals used to maximize and protect crops do not have unintended adverse consequences to bees. Flupyradifurone is a butenolide neonicotinoid used on crops affected by sucking pest insects that are resistant to other neonicotinoids. Recently, it has been shown that the leafcutter bee (Megachile rotundata), is 170-fold more sensitive to flupyradifurone than other managed bee pollinators. Further, evidence suggests that the pesticide tolerance of certain bee species is due to metabolism by specific P450 enzymes in the CYP9Q and CYP9BU subfamilies. A new approach method that can be used to computationally understand flupyradifurone susceptibility across insect species, and more specifically bee species, is the US EPA Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS) tool. The SeqAPASS tool allows users to rapidly evaluate available protein target sequence and structural similarity at the primary amino acid sequence, conserved domain(s), and individual amino acid residue levels, to understand conservation and therefore predict chemical susceptibility. Using the individual amino acid residue comparison feature of SeqAPASS allows for the identification of species-specific predictions of chemical susceptibility. A case study was developed comparing bees of differing sensitivities to flupyradifurone to explore possible individual differences in amino acid residues in the CYP9Q3 protein. Critical amino acid residues from the catalytic pocket of CYP9Q3 were compared across species. Although there is limited sequences available for key bee species, a critical lysine residue (K219) was identified as important for certain pesticide-CYP9Q interactions. An individual amino acid residue SeqAPASS evaluation predicted dissimilarity in susceptibility between the leafcutter bee and other managed bee pollinators due to a difference in the critical amino acid located at position 219. Through a review of available literature, along with computational assessments of susceptibility using the SeqAPASS tool, this study provides lines of evidence for differences in pesticide susceptibility among managed bee pollinators based on conservation of the CYP9 enzymes. In addition, this work demonstrates the ability of the SeqAPASS tool to rapidly identify differences in chemical susceptibility across other species of concern.
URLs/Downloads:
DOI: Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS) to understand chemical susceptibility across bee species.