Gene Function and Transcription

One-gene, one-enzyme hypothesis

each gene encodes information to produce an enzyme

Prototrophs (wild-type, non-mutant)

a by producing all the essential biological
chemicals from the compounds in the minimal media
using metabolic pathways

Minimal medium:

inorganic salts, nitrogen, carbon
source-sucrose and a vitamin biotin

Auxotrophs (mutants):

unable to grow on minimal
media because of a mutation in a metabolic gene that
converts compounds in minimal media

Arginine

an essential amino acid