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The influence of two-dimensional organization on peptide conformation.

ABSTRACT: Molecular crowding plays a significant role in regulating molecular conformation in cellular environments. It is also likely to be important wherever high molecular densities are required, for example in surface-phase studies, in which molecular densities generally far exceed those observed in solution. Using on-surface circular dichroism (CD) spectroscopy, we have investigated the structure of a synthetic peptide assembled into a highly packed monolayer. The immobilized peptide undergoes a structural transition between ?-helical and random coil conformation upon changes in pH and ionic concentration, but critically the threshold for conformational change is altered dramatically by molecular crowding within the peptide monolayer. This study highlights the often overlooked role molecular crowding plays in regulating molecular structure and function in surface-phase studies of biological molecules.

SUBMITTER: White SJ

PROVIDER: S-EPMC4506555 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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The influence of two-dimensional organization on peptide conformation.

White Simon J SJ Johnson Steven D SD Sellick Mark A MA Bronowska Agnieszka A Stockley Peter G PG Wälti Christoph C

Angewandte Chemie (International ed. in English) 20141120 3

Molecular crowding plays a significant role in regulating molecular conformation in cellular environments. It is also likely to be important wherever high molecular densities are required, for example in surface-phase studies, in which molecular densities generally far exceed those observed in solution. Using on-surface circular dichroism (CD) spectroscopy, we have investigated the structure of a synthetic peptide assembled into a highly packed monolayer. The immobilized peptide undergoes a stru ...[more]

PMID: 25413024

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