Modified i(E.coli) enterotoxin II signal peptide and microorganism expressing fusion protein of said peptide and heterologous protein

Abstract

A heterologous protein is produced by: (i) culturing a microorganism transformed with an expression vector comprising a gene encoding a modified E. coli enterotoxin II signal peptide fused with the heterologous protein to produce and secrete the heterologous protein to periplasm, the modified E. coli enterotoxin II signal peptide being obtained by replacing at least one of the 2nd, 4th, 5th, 12th, 20th, and 22nd amino acids of E. coli enterotoxin II signal peptide of the following amino acid sequence (SEQ ID NO: 1) with another amino acid, with the proviso that at least one of the 2nd and 4th amino acid of the modified peptide is lysine; and (ii) recovering the heterologous protein from the periplasm.

Description

field of invention

[0001] The present invention relates to a modified Escherichia coli endotoxin II signal peptide, a gene encoding the peptide, a vector comprising the gene fused together with a gene encoding a heterologous protein, a microorganism transformed with the vector, and the preparation of The method of said heterologous protein. Background of the invention

[0002] Many heterologous proteins have been produced by intracellular or secretory methods using genetically engineered host microorganisms.

[0003] In the intracellular approach, genes encoding heterologous proteins are expressed and accumulated in the cytoplasm of the microorganism. Although this method is known to yield higher yields of heterologous protein, the expressed heterologous protein is not in the native active form but is amino-terminally methioninated. In addition, biologically inactive heterologous proteins prepared by this method often form insoluble inclusion bodies, which must be solubili...

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