Method for secretory production of protein

A method for producing a heterologous protein comprising:

• culturing a coryneform bacterium comprising a genetic construct that allows for expression and secretion of a heterologous protein;
• and
• collecting the secreted heterologous protein,
• wherein the coryneform bacterium has been modified to comprise a polynucleotide encoding a mutant phosphate sensor kinase (PhoS) protein,
• wherein the mutant PhoS protein has PhoS sensor kinase activity and comprises an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO:
• 4, and wherein the tryptophan residue at the position corresponding to amino acid 302 of SEQ ID NO:
• 4 in the amino acid sequence of the mutant PhoS protein is replaced with an amino acid residue
• selected from the group consisting of lysine, alanine, valine, serine, cysteine, methionine, aspartic acid, and asparagine,
• wherein the genetic construct comprises, in the direction from 5′ to 3′, a promoter sequence that is able to function in the coryneform bacterium, a nucleic acid sequence encoding a signal peptide that is able to function in the coryneform bacterium, and a nucleic acid sequence encoding the heterologous protein, and
• wherein the heterologous protein is expressed as a fusion protein with the signal peptide.