Yeast Auxotrophic Selection (−Leu): Selects and maintains leucine-prototrophic (LEU2+) transformants on SD with 2.0% Glucose and 0.5% Ammonium Sulfate.

Plasmid Maintenance in S. cerevisiae: Ensures selection of LEU2-marked plasmids in yeast using defined SD −Leu plates.

Yeast Two-Hybrid (Y2H) Screening: Selects bait/prey constructs carrying LEU2 markers; 2.0% Glucose supports growth while repressing GAL-driven backgrounds.

CRISPR/Cas9 Editing Selection: Recovers genome-edited yeast using LEU2 selectable markers on SD −Leu.

Replica Plating and Spot Assays: Compares growth phenotypes and verifies leucine auxotrophy/prototrophy on defined −Leu medium.

Genetic Crosses and Diploid Selection: Selects diploids or segregants complementing LEU2 on SD −Leu plates.

Library and Mutant Screen Selection: Applies dropout selection to identify clones retaining LEU2 in combinatorial libraries.

Colony Isolation and Maintenance: Streaks, isolates, and passages LEU2+ yeast strains while preventing loss of selection.

Functional Assays Under Glucose Repression: Uses 2.0% Glucose to repress GAL promoters during reporter or pathway tests on −Leu medium.

Quality Control of Transformations: Confirms transformation efficiency and marker integrity on SD Modified Agar −Leu.