Mutations and Mutagenesis

Abstract

The first problem facing early bacterial geneticists was to prove that bacteria did have inherited traits. The earliest presumption was that bacteria and other microorganisms were too small to have any phenotypic traits that could be studied. That concept was disabused by the work of George Beadle and Edward Tatum, who demonstrated that biochemical reactions could be used as phenotypic traits and then developed the famous “one gene—one enzyme” hypothesis. There was, however, one remaining area of uncertainty regarding bacterial genetics. Many workers thought that the hypothesis of Lamarck regarding inheritance of acquired traits was true for bacteria even though it had already been disproved for animals and plants. The first task of the fledgling science of bacterial genetics was to prove that the same processes of mutation that had already been shown to occur in eukaryotes also occurred in prokaryotes. Recently, this controversy has arisen again in a new and particularly interesting form.