Practice question

In microbial genetics Beadle and Tatum defined prototroph as wild-type strain capable of growth on minimal medium containing only inorganic salts, carbon source, and biotin requirements, because its genome encodes complete biosynthetic pathways for all essential metabolites like amino acids, vitamins, purines. Prototrophs synthesize compounds de novo from simple precursors. They represent parental wild-type phenotype against which auxotrophic mutants blocked in specific pathways are scored. Prototroph selection on minimal plates underpins genetic mapping of mutations, recombination analysis, and complementation tests in bacteria and Neurospora.