Tert butylhydroperoxide tbooh

C. albicans strains were grown overnight in YPD at 30°C diluted to 2.5 × 10⁵ cells and then spread onto the surface of a synthetic complete medium agar plate. Ten microliters of each compound was applied to paper filter disks (Becton, Dickinson and Company, Sparks, MD), the disks were applied to the plate surface, incubated at 30°C for 48 h, and then the diameter of the zone of growth inhibition (halo) was measured. Compounds tested included p-benzoquinone (Sigma-Aldrich, St. Louis, MO), menadione (Sigma-Aldrich, St. Louis, MO), 2-tert-butyl-1,4-benzoquinone (Cayman Chemical, Ann Arbor, MI), hydrogen peroxide (Sigma-Aldrich, St. Louis, MO), tert-butyl-hydroperoxide (tBOOH; Acros Organics) and diamide (Sigma-Aldrich, St. Louis, MO). For the CFU assays, wild-type and the 3×GFP-tagged strains were grown overnight, harvested by centrifugation, and resuspended in PBS. A total of 1 × 10⁷ cells/mL were inoculated in liquid YPD and treated with one of the following: 100 µM of p-benzoquinone, 100 µM 2-tert-butyl-1,4-benzoquinone, 100 µM menadione, or 500 µM of hydrogen peroxide. Tubes were incubated for 1 h at 30°C on a tube roller, after which cultures were centrifugated and cells washed twice with PBS. Serial dilutions were plated on YPD plates, incubated for 48 h at 30°C, and then colony-forming units were counted.

Monensin A (95%) was sourced from Sigma-Aldrich Chemical Co. The Jacobsen catalyst, 3-chloroperoxybenzoic acid (m-CPBA), and tert-butyl hydroperoxide (t-BOOH, 70% solution in water) were all acquired from Acros-Organics. Hydrogen peroxide (30% in water) was supplied by Fluka and stored at 5°C, and it was periodically titrated to confirm its purity. Iodosylbenzene (PhIO) was obtained through iodosyl benzenediacetate hydrolysis and its purity was measured by iodometric assay.