DNA segment containing streptomycin resistance gene and being capable of controlling expression of said gene

摘要

A DNA segment of this invention is a DNA fragment of a length of about 3.8 kb which is obtained by excising with a restriction endonuclease Bgl II a hybrid plasmid pST 141 having a length of about 12.6 kb of Streptomyces griseus 4-1 strain (FERM P-7984, namely, FERM BP-1198) to give a Bgl II-Bgl II DNA fragment, and then excising with a restriction endonuclease Sph I the resultant Bgl II-Bgl II DNA fragment having a length of about 7.0 kb and having the restriction endonuclease sites as shown in the restriction endonuclease map of FIG. 1 . This DNA fragment is a DNA which contains a streptomycin resistance gene and contains, in the vicinity of this gene, such a DNA region possessing a function to control the expression of the streptomycin resistance gene. An insertion of this DNA fragment having a length of about 3.8 kb into a suitable actinomycetes plasmid vector can produce such a hybrid plasmid which acts reliably as a selected marker of the streptomycin resistance.