Neurospora can grow in minimal medium if it is not mutated
they can synthesise the enzyme which is needed to produce amino acids
Beadle and Tatum had grow Neurospora in minimal culture
Then, they exposed the Neurospora with X-ray caused mutation in Neurospora
They found that mutated Neurospora unable to grow in minimal medium because gene that codes for the synthesis of enzyme used to produce certain amino acid is mutated
The mutated neurospora only grew in complete culture which contain all 20 amino acid
Thus they isolate the mutated neurospora and grew them in minimal medium with a type of amino acid
Altogether there are 20 minimal medium with 20 different amino acid each
They found that neuropspora can only grew in presence of particular amino acid which is arginine
They had made one gene one enzyme hypothesis means the gene that code for the synthesis of enzyme that required to make arginine is mutated
One gene one enzyme hypothesis is then modified to one gene one protein hypothesis as the gene coiled code for other protein not necessary arginine
When it is found out that a protein can consist of more than one polypeptide chain
The hypothesis is further refined to one gene one polypeptide hypothesis
diagram a & b from
Using Microbiology to Discover the Secrets of Life | Microbiology (lumenlearning.com)
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