Streptavidin secretion by Streptomyces lividans strains

Recombinant strains of S. lividans capable of secreting streptavidin were isolated. Various constructions containing either streptavidin gene copies integrated within a chromosome or a streptavidin gene within the secretory vector were investigated. S. lividans SA2 containing a gene copy integrated within the chromosome had the maximum productivity amounting to 60-80 per cent of the S. avidinii productivity. New vectors for Streptomyces used in the study are described.