The Structure of the Diatom Silaffin Peptide R5 within Freestanding Two‐Dimensional Biosilica Sheets. Issue 28 (13th June 2017)

• Record Type: Journal Article
• Authors: Lutz, Helmut; Jaeger, Vance; Schmüser, Lars; Bonn, Mischa; Pfaendtner, Jim; Weidner, Tobias
• Is Part Of: Angewandte Chemie international edition. Volume 56:Issue 28(2017)
• Page Start: 8277
• Page End: 8280
• Publication Date: 2017-06-13
• Subjects: biomineralization -- molecular dynamics simulations -- peptides -- silica -- sum-frequency generation spectroscopy; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201702707
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The silaffin peptide R5 is instrumental to the mineralization of silica cell walls of diatom organisms. The peptide is also widely employed in biotechnology, for example, in the encapsulation of enzymes and for fusion proteins in tissue regeneration. Despite its scientific and technological importance, the interfacial structure of R5 during silica precipitation remains poorly understood. We herein elucidate the conformation of the peptide in its active form within silica sheets by interface‐specific vibrational spectroscopy in combination with molecular dynamics simulations. Contrary to previous solution‐state NMR studies, our data confirm that R5 maintains a defined structure when interacting with extended silica sheets. We show that the entire amino acid sequence of R5 interacts with silica during silica formation, leading to the intercalation of silica into the assembled peptide film. Abstract : Biosilica windows : The diatom silaffin peptide R5 was used to fabricate freestanding, nanometer‐thin biosilica sheets. These provided a realistic model system to determine the mode of action by which R5 fabricates extended silica structures by using sum‐frequency generation and molecular dynamics simulations.