摘要 |
<p>A triple mutant strain of Bacillus is described. The mutant strain has at least the phenotype Apr?-, Npr- SpoOH-¿ and shows a reduced level of extracellular proteases. The reduction in the level of the extracellular proteases secreted by the Bacillus cell makes it a useful host for the expression of heterologous polypeptides.</p> |