Insulin analogues with chlorinated amino acids
An insulin analogue comprises a B-chain polypeptide incorporating a chlorinated phenylalanine. The chlorinated phenylalanine may be located at position B24. The chlorinated phenylalanine may be para-monochloro-phenylalanine. The analogue may be of a mammalian insulin, such as human insulin. A nucleic acid encodes such an insulin analogue. The chlorinated insulin analogues retain significant activity. A method of treating a patient comprises administering a physiologically effective amount of the insulin analogue or a physiologically acceptable salt thereof to a patient. Chlorine substitution-based stabilization of insulin may reduce fibrillation and thereby enhance the treatment of diabetes mellitus in regions of the developing world lacking refrigeration.
1. An insulin analogue comprising a B-chain polypeptide incorporating a chlorinated phenylalanine, wherein the analogue displays at least one property, compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine, selected from the group consisting of:
improved resistance to fibril formation at room temperature;
at least two-fold improved resistance to fibril formation at room temperature in a zinc-free solution;
decreased cross-binding to Insulin-Like Growth Factor 1 Receptor;
accelerated rate of hexamer disassembly; and
at least 30 percent of the affinity to insulin receptor.
2. The insulin analogue of claim 1 , wherein the chlorinated phenylalanine is located at position B24.
3. The insulin analogue of claim 2 , wherein the chlorinated phenylalanine is para-monochloro-phenylalanine.
4. The insulin analogue of claim 3 , wherein the analogue is an analogue of a mammalian insulin.
5. The insulin analogue of claim 4 , wherein the analogue is an analogue of human insulin.
6. The insulin analogue of claim 4 , wherein the analogue comprises an amino acid sequence selected from the group consisting of SEQ ID NOS: 4-8 and polypeptides having three or fewer additional amino acid substitutions thereof.
7. The insulin analogue of claim 1 , wherein the analogue is an analogue of a mammalian insulin.
8. The insulin analogue of claim 1 , wherein the insulin analogue displays improved resistance to fibril formation at room temperature compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine.
9. The insulin analogue of claim 1 , wherein the insulin analogue displays at least two-fold improved resistance to fibril formation at room temperature compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine.
10. The insulin analogue of claim 1 , wherein the insulin analogue displays at least two-fold improved resistance to fibril formation at room temperature in a zinc-free solution compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine.
11. The insulin analogue of claim 1 , wherein the insulin analogue displays decreased cross-binding to Insulin-Like Growth Factor 1 Receptor compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine.
12. The insulin analogue of claim 1 , wherein the insulin analogue displays decreased cross-binding to Insulin-Like Growth Factor 1 Receptor compared to a corresponding wild type insulin.
13. The insulin analogue of claim 1 , wherein the insulin analogue displays an accelerated rate of hexamer disassembly compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine.
14. The insulin analogue of claim 1 , wherein the insulin analogue displays at least 30 percent of the affinity to insulin receptor compared to a corresponding wild type insulin.
15. The insulin analogue of claim 1 , wherein the analogue displays two or more properties, compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine, selected from the group consisting of:
improved resistance to fibril formation at room temperature;
at least two-fold improved resistance to fibril formation at room temperature in a zinc-free solution;
decreased cross-binding to Insulin-Like Growth Factor 1 Receptor;
accelerated rate of hexamer disassembly; and
at least 30 percent of the affinity to insulin receptor.
16. A method of lowering the blood sugar level of a patient comprising administering a physiologically effective amount of an insulin analogue or a physiologically acceptable salt thereof to the patient, wherein the insulin analogue or a physiologically acceptable salt thereof contains a B-chain polypeptide incorporating a chlorinated phenylalanine, wherein the analogue displays at least one property, compared to a corresponding insulin analogue that contains a non-chlorinated phenylalanine, selected from the group consisting of:
improved resistance to fibril formation at room temperature;
at least two-fold improved resistance to fibril formation at room temperature in a zinc-free solution;
decreased cross-binding to Insulin-Like Growth Factor 1 Receptor;
accelerated rate of hexamer disassembly; and
at least 30 percent of the affinity to insulin receptor.
17. The method of claim 16 , wherein the chlorinated phenylalanine is located at position B24.
18. The method of claim 17 , wherein the chlorinated phenylalanine is para-monochloro-phenylalanine.
19. The method of claim 18 , wherein the analogue comprises an amino acid sequence selected from the group consisting of SEQ. ID. NOS. 4-8 and polypeptides having three or fewer additional amino acid substitutions thereof.