Patent ID: 8518668

Claim:
A method for making mature human insulin or an analogue thereof comprising: culturing a fungal cell comprising a DNA sequence encoding a precursor for human insulin or an analogue of human insulin, wherein the precursor comprises a B-chain of human insulin or an analogue thereof, an A-chain of human insulin or an analogue thereof, and a C-peptide linking the B-chain and the A-chain, the C peptide comprising the sequence, X 1 -X 2 -Z-X 3 -X 4 wherein X 1 is a peptide sequence of 2 amino acid residues which may be the same or different and which are selected from the group consisting of Phe, Leu, Ile, Val, and Ala, X 2 is a Kex2 cleavage site, Z is an amino acid or a peptide sequence with from 2 to about 35 amino acid residues or a peptide bond, X 3 is a Kex2 cleavage site, and X 4 is a peptide bond, and isolating the desired product from the culture medium.