10.3389/fpls.2019.00568.s001 Gulab Rangani Gulab Rangani Reiofeli A. Salas-Perez Reiofeli A. Salas-Perez Raphael A. Aponte Raphael A. Aponte Michael Knapp Michael Knapp Ian R. Craig Ian R. Craig Thomas Mietzner Thomas Mietzner Ana Claudia Langaro Ana Claudia Langaro Matheus M. Noguera Matheus M. Noguera Aimone Porri Aimone Porri Nilda Roma-Burgos Nilda Roma-Burgos Data_Sheet_1_A Novel Single-Site Mutation in the Catalytic Domain of Protoporphyrinogen Oxidase IX (PPO) Confers Resistance to PPO-Inhibiting Herbicides.PDF Frontiers 2019 Amaranthus palmeri computational modeling cross-resistance Palmer amaranth PPO inhibitors PPO mutation protoporphyrinogen oxidase target-site resistance 2019-05-15 16:00:40 Dataset https://frontiersin.figshare.com/articles/dataset/Data_Sheet_1_A_Novel_Single-Site_Mutation_in_the_Catalytic_Domain_of_Protoporphyrinogen_Oxidase_IX_PPO_Confers_Resistance_to_PPO-Inhibiting_Herbicides_PDF/8132750 <p>Protoporphyrinogen oxidase (PPO)-inhibiting herbicides are used to control weeds in a variety of crops. These herbicides inhibit heme and photosynthesis in plants. PPO-inhibiting herbicides are used to control Amaranthus palmeri (Palmer amaranth) especially those with resistance to glyphosate and acetolactate synthase (ALS) inhibiting herbicides. While investigating the basis of high fomesafen-resistance in A. palmeri, we identified a new amino acid substitution of glycine to alanine in the catalytic domain of PPO2 at position 399 (G399A) (numbered according to the protein sequence of A. palmeri). G399 is highly conserved in the PPO protein family across eukaryotic species. Through combined molecular, computational, and biochemical approaches, we established that PPO2 with G399A mutation has reduced affinity for several PPO-inhibiting herbicides, possibly due to steric hindrance induced by the mutation. This is the first report of a PPO2 amino acid substitution at G399 position in a field-selected weed population of A. palmeri. The mutant A. palmeri PPO2 showed high-level in vitro resistance to different PPO inhibitors relative to the wild type. The G399A mutation is very likely to confer resistance to other weed species under selection imposed by the extensive agricultural use of PPO-inhibiting herbicides.</p>