at Google ScholarTitle data
Siedlecka, Monika ; Goch, Grażyna ; Ejchart, Andrzej ; Sticht, Heinrich ; Bierzyǹski, Andrzej:
α-Helix nucleation by a calcium-binding peptide loop.
In: Proceedings of the National Academy of Sciences of the United States of America.
Vol. 96
(1999)
Issue 3
.
- pp. 903-908.
ISSN 1091-6490
DOI: https://doi.org/10.1073/pnas.96.3.903
Abstract in another language
A 12-residue peptide AcDKDGDGYISAAENH2 analogous to the third calcium-binding loop of calmodulin strongly coordinates lanthanide ions (K = 105 M−1). When metal saturated, the peptide adopts a very rigid structure, the same as in the native protein, with three last residues AAE fixed in the α-helical conformation. Therefore, the peptide provides an ideal helix nucleation site for peptide segments attached to its C terminus. NMR and CD investigations of peptide AcDKDGDGYISAAEAAAQNH2 presented in this paper show that residues A13-Q16 form an α-helix of very high stability when the La3+ ion is bound to the D1-E12 loop. In fact, the lowest estimates of the helix content in this segment give values of at least 80% at 1°C and 70% at 25°C. This finding is not compatible with existing helix-coil transition theories and helix propagation parameters, s, reported in the literature. We conclude, therefore, that the initial steps of helix propagation are characterized by much larger s values, whereas helix nucleation is even more unfavorable than is believed. In light of our findings, thermodynamics of the nascent α-helices is discussed. The problem of CD spectra of very short α-helices is also addressed.
Further data
| Item Type: | Article in a journal |
|---|---|
| Refereed: | Yes |
| Institutions of the University: | Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Former Professors > Chair Biopolymers - Univ.-Prof. Dr. Paul Rösch Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Former Professors Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Biochemistry with an Emphasis on Biophysical Chemistry |
| Result of work at the UBT: | Yes |
| DDC Subjects: | 500 Science > 540 Chemistry 500 Science > 570 Life sciences, biology |
| Date Deposited: | 23 Jan 2019 11:13 |
| Last Modified: | 05 Sep 2022 07:28 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/46999 |