Cloning and expression of the gene encoding the glutamic acid-specific protease of Streptomyces griseus ATCC10137.

The gene (sgpE) encoding the Streptomyces griseus glutamic-acid-specific protease (SGPE) was cloned and sequenced. The sgpE gene contained an open reading frame of 1065 nucleotides encoding 355 amino acids (aa) with a pre-propeptide of 168 aa ending at Glu, suggesting the probability of auto-proteolysis. A Streptomyces lividans strain carrying the plasmid-borne sgpE under control of the traA gene promoter secreted mature SGPE into the culture medium. Compared to Staphylococcus aureus protease V8, the purified SGPE was more resistant to urea. It is suggested that SGPE would be a useful tool for site-specific processing of proteins, even under denaturing conditions.