Module 8: Classic Genetics

• wild type: specific strain chosen arbitrarily as reference
• mutant: strain of species with different genotype than wild type
• selection: conditions where only mutant of interest can grow
• what is an example of selection?

  growing antibiotic resistant mutant in medium with antibiotic
• when does mutation occur in selection?

  mutation happens before selection and selective pressure reveals mutants
• screens: most cells grow and desired mutant is detectably differnt
• screen types:

  1. assay of enzyme
  2. replica plates
  3. color indicator plates
• assay of enzyme: have to develop many colonies and assay to find desired enzyme activity result
• replica plates: transfer imprint of colonies to minimal plate to determine if they can synthesize
• color indicator plates: mutant reacts by color change