| 摘要 |
Mutants can be obtained in a very simple fashion by isolating the entire DNA from the strain to be mutated, cleaving this DNA into small fragments and integrating it into a temperature-sensitive plasmid using a further selection marker, transforming the resulting hybrid plasmid population into the original strain, selecting the transformants by selection for the marker, eliminating the hybrid plasmids by increasing the temperature above the threshold value of the temperature-sensitive plasmid, and selecting the mutants by reselection for the marker. Since the mutated gene is marked in this manner, it can be isolated easily and the unmutated gene can be isolated from a gene bank of the wild type by hybridisation. |
