[Cloning of streptavidin gene from Streptomyces avidinii and its expression in Escherichia coli. Secretion of streptavidin by E. coli cells]. / Klonirovanie gena streptavidina iz Streptomyces avidinii i ego ékspressiia v Escherichia coli. Sekretsiia streptavidina kletkami E. coli.

The streptavidin gene from Streptomyces avidinii was cloned, an expression plasmid constructed, and a highly effective strain producer of streptavidin created. It was shown that the leader peptide of streptavidin ensures the effective secretion of this protein into the periplasmic space of Escherichia coli cells. The degradation site of the leader peptide was detected. Upon treatment with the total fraction of proteases secreted by S. avidinii into the culture medium, "core" streptavidin was obtained, which retained the biotin-binding function.