Bacterial positive selection vector

摘要

PCT No. PCT/US96/17636 Sec. 371 Date Apr. 30, 1998 Sec. 102(e) Date Apr. 30, 1998 PCT Filed Oct. 31, 1996 PCT Pub. No. WO97/16558 PCT Pub. Date May 9, 1997A positive selection vector is provided for the transformation and screening of Gram positive bacteria and particularly Bacillus sp. for the presence of foreign DNA. The vector comprises a mutant gene encoding a signal peptide processing mutation. Expression of the mutant gene in a Bacillus host cell which lacks the ability to metabolize sucrose is lethal when cells are grown in the presence of sucrose. Foreign DNA may be inserted into the vector so as to inactivate the mutant gene thereby permitting the cells to grow in the presence of sucrose and allowing for facile selection of transformants.