Abstract: There is disclosed a new calcium-regulated promoter to be used for increasing production of extracellular enzymes, or heterologous polypeptides, a recombinant vector that includes the DNA sequence of the promoter operatively linked to a DNA encoding said enzyme or polypeptide and a host organism transformed with the recombinant vector that includes the promoter operatively linked to the DNA encoding said enzyme or polypeptide. The present invention further relates to Streptomyces expression systems and methods for expressing foreign DNA sequences in Streptomyces and for secreting to the surrounding medium polypeptides and proteins coded for by those foreign DNA sequences.

Abstract: The cloning and characterization of a newly isolated gene, referred to as saf (secondary metabolism activation factor) is disclosed. This gene encodes a new amino acid polypeptide, referred to as the SAF polypeptide, which directly or indirectly modulates the expression of extracellular enzymes in Steptomyces. DNA units or fragments which encode the SAF polypeptide are also disclosed, as are vectors containing said DNA, host organisms transformed with such vectors, and processes for preparing extracellular enzymes or heterologous polypeptides by culturing such host organisms.

Abstract: The cloning and characterization of a newly isolated gene, referred to as saf (secondary metabolism activation factor) is disclosed. This gene encodes a new amino acid polypeptide, referred to as the SAF polypeptide, which directly or indirectly modulates the expression of extracellular enzymes in Streptomyces. DNA units or fragments which encode the SAF polypeptides are also disclosed, as are vectors containing said DNA, host organisms transformed with such vectors, and processes for preparing extracellular enzymes or heterologous polypeptides by culturing such host organisms.