Titlebar

Export bibliographic data
Literature by the same author
plus on the publication server
plus at Google Scholar

 

End-to-end distance distributions and intrachain diffusion constants in unfolded polypeptide chains indicate intramolecular hydrogen bond formation

Title data

Möglich, Andreas ; Joder, Karin ; Kiefhaber, Thomas:
End-to-end distance distributions and intrachain diffusion constants in unfolded polypeptide chains indicate intramolecular hydrogen bond formation.
In: Proceedings of the National Academy of Sciences of the United States of America. Vol. 103 (15 August 2006) Issue 33 . - pp. 12394-12399.
ISSN 1091-6490
DOI: https://doi.org/10.1073/pnas.0604748103

Abstract in another language

Characterization of the unfolded state is essential for the understanding of the protein folding reaction. We performed time-resolved FRET measurements to gain information on the dimensions and the internal dynamics of unfolded polypeptide chains. Using an approach based on global analysis of data obtained from two different donor-acceptor pairs allowed for the determination of distance distribution functions and diffusion constants between the chromophores. Results on a polypeptide chain consisting of 16 Gly-Ser repeats between the FRET chromophores reveal an increase in the average end-to-end distance from 18.9 to 39.2 Angstrom between 0 and 8 M GdmCl. The increase in chain dimensions is accompanied by an increase in the end-to-end diffusion constant from (3.6 +/- 1.0) x 10(-7) cm(2) s(-1) in water to (14.8 +/- 2.5) x 10(-7) cm(2) s(-1) in 8 M GdmCl. This finding suggests that intrachain interactions in water exist even in very flexible chains lacking hydrophobic groups, which indicates intramolecular hydrogen bond formation. The interactions are broken upon denaturant binding, which leads to increased chain flexibility and longer average end-to-end distances. This finding implies that rapid collapse of polypeptide chains during refolding of denaturant-unfolded proteins is an intrinsic property of polypeptide chains and can, at least in part, be ascribed to nonspecific intramolecular hydrogen bonding. Despite decreased intrachain diffusion constants, the conformational search is accelerated in the collapsed state because of shorter diffusion distances. The measured distance distribution functions and diffusion constants in combination with Szabo-Schulten-Schulten theory were able to reproduce experimentally determined rate constants for end-to-end loop formation.

Further data

Item Type: Article in a journal
Refereed: Yes
Additional notes: PubMed-ID: 9526123
Institutions of the University: Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Biochemistry > Chair Biochemistry - Univ.-Prof. Dr. Andreas Möglich
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 > Professorship Biochemistry
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Biochemistry
Result of work at the UBT: No
DDC Subjects: 500 Science > 540 Chemistry
Date Deposited: 20 May 2015 06:58
Last Modified: 20 May 2015 06:58
URI: https://eref.uni-bayreuth.de/id/eprint/13611