Mutation: Site-Directed Mutagenesis (Reversed Genetics)

摘要: The recent revolution in biology, which is best described by the term “genetic engineering”, has also revolutionized area of mutagenesis. In “classical” or conventional approach to mutagenizing a gene genes, entire virus, whole organism its total DNA case transformable organisms was treated with mutagen. Mutants desired characteristics were then either selected from large number individuals screened time-consuming operations. resulting mutants could be characterized and used for mapping other genetic studies. However, biochemical investigations reasonable only when extensive clearly proved that mutations one result mutagenization process. Especially investigation regulation expression, e.g., differentiation, critical obtained this kind mutant construction used. Secondary not excluded entirely, often obscured falsified results (pleiotropic effect). Therefore, characterizations necessary prior use these mutants. some bacteria (e.g., Bacillus subtilis), purification successive transformations wild-type subsequent screening many colonies allowed generation sets isogenic strains (HOCH, 1976).