SC-Ura, also known as Hopkins Mixture, is a single dropout formulation of Synthetic Complete Supplement Mixture (SC) of amino acids for S. cerevisiae growth media.
Reagents are tested and chosen for their ability to promote optimum growth of yeast strains when combined in the Drop Out Base (DOB) or Drop Out Base with 17 g Agar (DOBA) formula, with SC-Ura. DOB contains 1.7 g Yeast Nitrogen Base, 5 g Ammonium Sulfate, and 20 g Dextrose per liter. Chosen reagents are combined in the proper proportions according to the formulation listed on the Certificate of Analysis and milled to thoroughly blend the reagents for a uniform distribution. A sample of the milled and blended formulation was used to prepare liquid medium by adding 43.7 g DOBA powder and 1.9 g of SC-Ura to a liter of purified water. The combinations were mixed by hand for about 1 minute to dissolve the dextrose and autoclaved at 121°C for 15 minutes. After cooling to 50°C, plates were poured. DOBA with SC-Ura liquid solution was visually inspected after autoclaving and pouring plates for complete dissolution of components. Solid plates were inoculated with control S.cerevisiae yeast strain and incubated for 3 days at 30°C. Colony size was compared to the same strain grown on standard lot test media (SLTM).