Attenuated pathogen which includes variations in a Gene essential for the biosynthesis of diaminopimelico acid, method for selecting these microorganismsVacunaque contains and Method for Inducing immune protection against it.

摘要

The Invention comprises methods for maintaining desired Genetic recombinant Gene in a population of cells that express the desired Gene.Methods Using microbial cells is an inactivating mutation in a Gene that encodes an essential Native Enzyme that catalyzes one step in the biosynthesis of diaminopimelico acid(DAP). The cells also have an extrachromosomal vector that includes the desired Gene, which is capable of homologous recombination with the chromosome of the microorganism.Elvector also has a complementary recombinant Gene encodes a functional replacement of the native Gene is essential.The cells of the invention are particularly useful as Vaccine components, including DNA vaccines.