Paraquat dichloride hydrate paraquat

The wild-type strain and the msh2Δ, mlh1Δ, and pms1Δ mutants were streaked for single colonies on YPD medium or YPD medium-nourseothricin (100 µg/ml) plates and incubated at 28°C. Single colonies were restreaked every 7 days for 2 months (approximately 600 generations). Three independent strains were generated for the wild-type strain and each mutant (Table S2). Strains were then cultured overnight using YPD medium, 10-fold serially diluted, and plated onto YPD medium with or without the following stress agents: 0.25 mM paraquat dichloride hydrate (paraquat) (Sigma-Aldrich; catalog no. 36541), 5 mM hydrogen peroxide solution (H₂O₂) (Sigma-Aldrich; catalog no. 216763), 1.5 mg/ml calcofluor white, and 5 mg/ml Congo red. Plates were incubated at 28°C for 2 days. One set of plates was incubated at 37°C. Strains were also plated on l-DOPA (l-3,4-dihydroxyphenylalanine) medium to assess melanization.

Strains were cultured overnight in YPD medium, 10-fold serially diluted, and plated onto YPD medium with or without the following stress agents: 0.04% methyl methanesulfonate (MMS) (Sigma-Aldrich; catalog no. 129925), 0.06% ethidium bromide solution (EtBr) (Sigma-Aldrich; catalog no. E1510), 0.25 mM menadione (Sigma-Aldrich; catalog no. M5625), 0.25 mM paraquat dichloride hydrate (paraquat) (Sigma-Aldrich; catalog no. 36541), 0.4 mM Luperox TBH70X tert-butyl hydroperoxide solution (tBOOH) (Sigma-Aldrich; catalog no. 458139), and 5 mM hydrogen peroxide solution (H₂O₂) (Sigma-Aldrich; catalog no. 216763). One set of plates was exposed to UV light (120 J m⁻²). Plates were incubated at 28°C for 2 days.