Patent ID: 6841361

Claim:
A DNA encoding a fusion protein of formula (I): [Y]-[X1]-[B-chain]-[X2]-[Linker]-[X3]-[A-chain] (I) wherein Y is a leader peptide sequence for expression and secretion of the protein, comprising the N-terminal 9 amino acid residues of the middle wall protein (MWP) which is one of the cell wall proteins (CWPs) from a bacterium belonging to the genus Bacillus; X1 is an amino acid sequence which is cleavable with thrombin; B-chain is the amino acid sequence of insulin B chain; X2 is an amino acid sequence which is cleavable with thrombin Linker is a linker sequence comprising at least one amino acid residue; X3 is an amino acid sequence which is cleavable with thrombin; and A-chain is the amino acid sequence of insulin A chain, and wherein the Y, X1, B-chain, X2, Linker, X3 and A-chain are ligated in the order indicated in formula (1).