Crystals of LmPTR1 were prepared as described elsewhere. The LmPTR1-cofactor-2e ternary complex was obtained by the soaking technique, adding 2 mM compound (solubilized in DMSO, without exceeding the 10% drop volume) directly into the crystallization drop. After 5 h, crystals were transferred to the cryoprotectant solution and flash frozen in liquid nitrogen.