Trimethylation of the R5 Silica-Precipitating Peptide Increases Silica Particle Size by Redirecting Orthosilicate Binding
| Autor: | Erika L. Buckle, Nina Michael, Samuel D. Whedon, Gary P. Drobny, Calvin Jon Antolin Leonen, Janani Sampath, Jim Pfaendtner, Champak Chatterjee |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Lysine
Silicic Acid Nanoparticle Peptide Molecular Dynamics Simulation 010402 general chemistry 01 natural sciences Biochemistry Methylation Article chemistry.chemical_compound Molecular dynamics Polymer chemistry Side chain Particle Size Protein Precursors Molecular Biology chemistry.chemical_classification Diatoms Aqueous solution Binding Sites 010405 organic chemistry Organic Chemistry Silicon Dioxide Peptide Fragments 0104 chemical sciences N-terminus chemistry Molecular Medicine Orthosilicate |
| Zdroj: | Chembiochem |
| ISSN: | 1439-7633 |
| Popis: | The unmodified R5 peptide from silaffin in the diatom Cylindrotheca fusiformis rapidly precipitates silica particles from neutral aqueous solutions of orthosilicic acid. A range of post-translational modifications found in R5 contribute toward tailoring silica morphologies in a species-specific manner. We investigated the specific effect of R5 lysine side-chain trimethylation, which adds permanent positive charges, on silica particle formation. Our studies revealed that a doubly trimethylated R5K3,4me3 peptide has reduced maximum activity yet, surprisingly, generates larger silica particles. Molecular dynamics simulations of R5K3,4me3 binding by the precursor orthosilicate anion revealed that orthosilicate preferentially associates with unmodified lysine side-chain amines and the peptide N terminus. Thus, larger silica particles arise from reduced orthosilicate association with trimethylated lysine side chains and their redirection to the N terminus of the R5 peptide. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text