Insight into the Supramolecular Architecture of Intact Diatom Biosilica from DNP-Supported Solid-State NMR Spectroscopy.
Diatom biosilica is an inorganic/organic hybrid with interesting properties. The molecular architecture of the organic material at the atomic and nanometer scale has so far remained unknown, in particular for intact biosilica. A DNP-supported ssNMR approach assisted by microscopy, MS, and MD simulations was applied to study the structural organization of intact biosilica. For the first time, the secondary structure elements of tightly biosilica-associated native proteins in diatom biosilica were characterized in situ. Our data suggest that these proteins are rich in a limited set of amino acids and adopt a mixture of random-coil and β-strand conformations. Furthermore, biosilica-associated long-chain polyamines and carbohydrates were characterized, thereby leading to a model for the supramolecular organization of intact biosilica.
Bioanalytical Chemistry, TU Dresden, Bergstraße 66, 01069 Dresden (Germany).
Anne
A
Jantschke
NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht (The Netherlands).
Eline
E
Koers
NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht (The Netherlands).
Deni
D
Mance
NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht (The Netherlands).
Markus
M
Weingarth
Bioanalytical Chemistry, TU Dresden, Bergstraße 66, 01069 Dresden (Germany). eike.brunner@tu-dresden.de.
Eike
E
Brunner
NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht (The Netherlands). m.baldus@uu.nl.
Marc
M
Baldus
D017377:Diatoms / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D056004:Molecular Dynamics Simulation; D010316:Particle Size; D012015:Reference Standards; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
D046911:Macromolecular Substances; D012822:Silicon Dioxide
DNP; biomineralization; diatoms; hybrid materials; solid-state NMR