Patent ID: 7803763

Claim:
A method for the chromatographic purification of preproinsulin of the formula 1, wherein X a) is a genetically encodable amino acid residue or b) is a peptide having from 2 to 35 amino acid residues, which starts and ends with in each case a basic amino acid residue, in particular Arg, and which, if it consists of more than 3 amino acid residues, starts and ends with in each case two basic amino acid residues, in particular Arg and/or Lys, R 1 a) is hydrogen, b) is a genetically encodable amino acid residue or c) is a peptide having from 2 to 15 amino acid residues, R 2 is a genetically encodable amino acid residue, and the residues A1-A20 correspond to the amino acid sequence of the A chain of human insulin or of an insulin analog and the residues B1-B30 correspond to the amino acid sequence of the B chain of human insulin or of an insulin analog; wherein said method for chromatographic purification of preproinsulin comprises: removing higher molecular weight substances from an aqueous solution of said preproinsulin by means of a first chromatography on an anion exchanger in flow-through mode and a subsequent second chromatography on a cation exchanger in adsorption mode and wherein said preproinsulin of formula (l) is consisting of the following amino acid sequence: (SEQ ID NO: 3) Ala-Thr-Thr-Ser-Thr-Gly-Asn-Ser-Ala-Arg-Phe-Val- Asn-Gln-His-Leu-Cys-Gly-Ser-His-Leu-Val-Glu-Ala- Leu-Tyr-Leu-Val-Cys-Gly-Glu-Arg-Gly-Phe-Phe-Tyr- Thr-Pro-Lys-Thr-Arg-Arg-Glu-Ala-Glu-Asp-Pro-Gln- Val-Gly-Gln-Val-Glu-Leu-Gly-Gly-Gly-Pro-Gly-Ala- Gly-Ser-Leu-Gln-Pro-Leu-Ala-Leu-Glu-Gly-Ser-Leu- Gln-Lys-Arg-Gly-Ile-Val-Glu-Gln-Cys-Cys-Thr-Ser- Ile-Cys-Ser-Leu-Tyr-Gln-Leu-Glu-Asn-Tyr-Cys-Gly and wherein X is a peptide chain having 35 amino acid residues with the sequence of simian C peptide, R1 is a peptide chain having 10 amino acid residues with the sequence Ala-Thr-Thr-Ser-Thr-Gly-Asn-Ser-Ala-Arg (SEQ ID NO: 5), R2 is the amino acid residue Gly, A1-A20 is a peptide chain with the sequence (only A1 to A20) of the A chain of human insulin, B1-B30 is a peptide chain having the sequence of the B chain of human insulin.