Patent ID: 8389264

Claim:
A recombinant Bacillus subtilis host cell comprising (a) a transfected gene encoding a desired protein or polypeptide, (b) a genetic modification to overexpress a secY gene of a Bacillus species in said recombinant Bacillus subtilis host cell as compared to expression of said secY gene in a Bacillus subtilis host cell that is the same except that it lacks said genetic modification of said secY gene, and (c) deletion, from the genome of said recombinant Bacillus subtilis host cell, of one or more sporulation-associated genes selected from the group consisting of the kinA gene, kinB gene, kinC gene, spo0F gene, spo0B gene, spo0A gene, kapB gene, kipA gene, phrA gene, spo0J gene, sigH gene, sigF gene, sigE gene, spoIIAA gene, spoIIAB gene, spoIIE gene, spoIIR gene, spoIIGA gene, sigG gene, spoIIIC gene, and spoIVCB gene, wherein secretion of said desired protein or polypeptide from said recombinant host cell is greater than the secretion achieved by either overexpression of said secY gene or deletion of said one or more sporulation-associated genes alone, wherein said secY gene is the only gene associated with the Sec route of B. subtilis that is overexpressed in said host cell, and wherein said genetic modification to overexpress said secY gene comprises introduction of: (i) a transcription initiation control region, or a transcription initiation control region and a ribosome binding site, that function in said host cell, upstream of said Bacillus species secY gene, or (ii) a transcription initiation control region, or a transcription initiation control region and a ribosome binding site, that function in said host cell, upstream of the leader gene of an operon containing said Bacillus species secY gene, or (iii) a gene fragment in which a transcription initiation control region, or a transcription initiation control region and a ribosome binding site, that function in said host cell, are linked upstream of said Bacillus species secY gene, wherein said transcription initiation control region or said transcription initiation control region and ribosome binding site of parts (i), (ii) and (iii) are from a B. subtilis spoVG gene or a B. subtilis aprE gene.