"One gene-one protein" hypothesis states that one gene codes for one protein while the "one gene-one polypeptide" hypothesis states that one gene codes for one polypeptide chain of a protein having more than one type of polypeptide chains.
Explanation:
Beadle and Tatum proposed the one gene-one protein concept to explain the one-to-one correspondence between genes and proteins. Accordingly, one gene carries information to encode one protein. Since enzymes are proteins with catalytic power, a gene encodes the information to produce a single enzyme.
The "one gene-one protein" concept was later modified into the "one gene-one polypeptide" hypothesis. According to the "one gene-one polypeptide" hypothesis, one protein may have more than one polypeptide chain. One gene carries the genetic information to encode one polypeptide. Therefore, a protein with more than one type of polypeptide chains will be encoded by more than one gene.
And that's going to happen someday! The Andromeda galaxy is currently racing toward our Milky Way at a speed of about 70 miles (110 km) per second. Ultimately, the two galaxies will collide and merge.
