Crystal structure of desheptapeptide(B24-B30)insulin at 1.6 A resolution: implications for receptor binding.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 9096331.
- Also identified by PMC identifier 20307.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The crystal structure of desheptapeptide (B24-B30) insulin (DHPI), a virtually inactive analog of insulin, was determined at 1.6 A resolution. In the refined structure model, DHPI retains three alpha-helices (A1-A8, A12-A18, and B9-B19) as its structural framework, while great conformational changes occur in the N and C termini of B-chain. The beta-turn, which lies in B20-B30 in insulin and insulin analogs with high potency, no longer exists in DHPI. Relative motion is observed among the three alpha-helices, each as a rigid functional group. In contrast, a region covering B5-B6 and A6-A11 exhibits a relatively stable conformation. We interpret our results as identifying: (i) the importance of beta-turn in determining the receptor-binding potency of insulin and (ii) a leading role of PheB24 in maintaining the beta-turn structure.
Medical subject headings
- Insulin
- Peptide Fragments