| 摘要 |
<p>A transformant selection system has been developed, particularly for a β-lactam producing strain, more particularly for P. chrysogenum, by the complementation of a mutation of said β-lactam producing strain by a homologous selection marker without interfering with β-lactam biosynthesis. Particularly, in applying said transformant selection system a positive selection agent, for instance fluoroacetate is used for the isolation of fac mutants of said strain, particularly of said β-lactam producing strain. Furthermore, a gene entitled facA has been isolated from P. chrysogenum.</p> |
