Genetic analysis and overexpression of lipolytic activity in Bacillus subtilis

The previously cloned Bacillus subtilis lipase gene (lip) was mapped on the chromosome and used in the construction of a B. subtilis derivative totally devoid of any lip sequence. Homologous overexpression was performed in this strain by subcloning the lip open reading frame on a multicopy plasmid under the control of a strong gram-positive promoter. A 100-fold overproducing strain was obtained, which should facilitate purification of the secreted protein. Furthermore, the delta lip strain BCL1050 constitutes an ideal host for the cloning of heterologous lipase genes.