In the 1940s,George Beadle and Edward Tatum developed the one-gene-one-polypeptide hypothesis by mutating the genes of Neurospora crassa (bread mold).They identified mutants that were unable to synthesize amino acids,such as arginine.When multiple mutant strains were identified for a single trait (adenine synthesis deficient),they showed that:
A)all the mutants encoded the same single enzyme.
B)genes were transcribed before being translated.
C)each step in the biochemical pathway was mediated by an enzyme encoded by a single gene.
D)the biosynthesis of arginine could occur,even with mutated enzymes.
E)separate genes/enzymes performed identical steps in the pathway.

Question

Quizplus · Accepted Answer

Beadle and Tatum showed that each step in the biosynthetic pathway of amino acids (such as arginine) was mediated by a specific enzyme encoded by a single gene. This led to the development of the one-gene-one-polypeptide hypothesis, which states that each gene codes for a single polypeptide chain (or a functional RNA). This concept was later modified to include some exceptions (such as alternative splicing and post-translational modifications) but still forms the basis of our understanding of the relationship between genes and proteins.

In the 1940s,George Beadle and Edward Tatum Developed the One-Gene-One-Polypeptide