GENE INTEGRATION INTO CHROMOSOMES OF LACTOBACILLUS DELBRUECKII SPECIES AND INTEGRANTS THEREOF

摘要

A gene to be integrated is bound to pAM.beta.1 plasmid to construct an integration plasmid, which is conjugally transferred into chromosomal DNA of a strain of Lactobacillus delbrueckii species. Integration of only the objective gene occurs through homologous recombination events (double crossing-over). According to this method, an arbitrary gene can be integrated into chromosomal DNA of a strain of Lactobacillus delbrueckii species and the DNA sequence derived from the vector, pAM.beta.1, can be completely removed. Therefore, the obtained gene integrant is widely applicable to the production of foods, medicines, feeds and the like. 51