Polycationic peptides from diatom biosilica that direct silica nanosphere formation.

  title={Polycationic peptides from diatom biosilica that direct silica nanosphere formation.},
  author={Nils Kr{\"o}ger and Rainer Deutzmann and Manfred Sumper},
  volume={286 5442},
Diatom cell walls are regarded as a paradigm for controlled production of nanostructured silica, but the mechanisms allowing biosilicification to proceed at ambient temperature at high rates have remained enigmatic. A set of polycationic peptides (called silaffins) isolated from diatom cell walls were shown to generate networks of silica nanospheres within seconds when added to a solution of silicic acid. Silaffins contain covalently modified lysine-lysine elements. The first lysine bears a… 

Biomimetic synthesis of silica nanospheres depends on the aggregation and phase separation of polyamines in aqueous solution

Long-chain polyamines extracted from the highly siliceous cell walls of diatoms are known to precipitate silica nanospheres from aqueous, silicic-acid containing solutions at near-neutral pH in

The Diatom Peptide R5 Fabricates Two-Dimensional Titanium Dioxide Nanosheets.

Diatoms use peptides based on the protein silaffin to fabricate their silica cell walls. To the interest of material scientists, silaffin peptides can also produce titanium dioxide nanoparticles.

The Structure of the Diatom Silaffin Peptide R5 within Freestanding Two-Dimensional Biosilica Sheets.

It is shown 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, contradicting previous solution-state NMR studies.


Condensation of silicic acid was studied in the presence of poly(vinylamine) fractions (238-11000 units). The reaction results in soluble nanoparticles or composite precipitates depending on

Silacidins: highly acidic phosphopeptides from diatom shells assist in silica precipitation in vitro.

A new class of aspartate/glutamate-rich and serine phosphate rich peptides as constituents of biosilica produced by the diatom Thalassiosira pseudonana is described, known as silacidins due to their presence in silica and their acidic nature.

Biomimetic silica formation: analysis of the phosphate-induced self-assembly of polyamines.

Solid-state 31P NMR studies on phase-separated polyamines, synthetic silica precipitates, and diatom cell walls from the species Coscinodicus granii support the assumption of a phosphate-induced phase separation process taking place during cell wall formation.

Nanosilica formation at lipid membranes induced by silaffin peptides

Diatoms are unicellular eukaryotic algae found in fresh and marine water. Each cell is surrounded by an outer shell called a frustule that is composed of highly structured amorphous silica. Diatoms

Self-Assembly in Biosilicification and Biotemplated Silica Materials

A more recent strategy based on the integration of biological self-assembly as the driving force of silica nanoparticles organization offers new perspectives to elaborate highly-tunable, biofunctional nanocomposites.

Tailored synthetic polyamines for controlled biomimetic silica formation.

A synthetic route based on solid-phase peptide synthesis is described from which well-defined long-chain polyamines with different chain lengths, methylation patterns, and subunits can be obtained and may pave the way for better control of the formation of nanostructured silica under ambient conditions.



Silicatein filaments and subunits from a marine sponge direct the polymerization of silica and silicones in vitro.

  • J. ChaK. Shimizu D. Morse
  • Chemistry
    Proceedings of the National Academy of Sciences of the United States of America
  • 1999
It is shown that the protein filaments and their constituent subunits comprising the axial cores ofsilica spicules in a marine sponge chemically and spatially direct the polymerization of silica and silicone polymer networks from the corresponding alkoxide substrates in vitro, under conditions in which such syntheses otherwise require either an acid or base catalyst.

Silicatein α: Cathepsin L-like protein in sponge biosilica

Structural features of the cDNA sequence of silicatein α, the most abundant of these subunits, reveals that this protein is highly similar to members of the cathepsin L and papain family of proteases, suggesting the possibility of a dynamic role of the silicateins in silicification of the sponge spicule.

The amino acid and sugar composition of diatom cell-walls

The amino acid and sugar composition of cell walls from 6 diatom species have been elucidated and Condensation of silicic acid, in epitaxial order, on a protein template enriched in serine and threonine, is suggested as the Si-depositing mechanism in diatoms.

Silicic Acid Polymerization Catalyzed by Amines and Polyamines

Amines, particularly polyamines, catalyzed the polycondensation of silicic acid in water. The resultant gel contained these polyamines with a N/Si molar ratio of up to 0.5. IR and powder X-ray stud...

Molecular tectonics in biomineralization and biomimetic materials chemistry

  • S. Mann
  • Chemistry, Materials Science
  • 1993
The systematic fabrication of advanced materials will require the construction of architectures over scales ranging from the molecular to the macroscopic. The basic constructional processes of

Frustulins: domain conservation in a protein family associated with diatom cell walls.

The complete primary structures of threecell wall proteins (denoted as frustulins) have been determined and a highly conserved domain has been identified as a common building block of diatom cell wall proteins that is repeated several times per polypeptide chain together with polyproline/hydroxyproline or polyglycine spacers.


The results with DAMP suggest that the pH of the SDV is important in the silicification of diatoms: It facilitates a fast nucleation and aggregation of silica particles, thus increasing the rate of formation of the mature frustules.

Characterization of a 200-kDa diatom protein that is specifically associated with a silica-based substructure of the cell wall.

A diatom cell wall protein (HEP200) is identified that is associated with a distinct substructure of the silica scaffold and is a member of a new protein family, of which two more members are identified.

A new calcium binding glycoprotein family constitutes a major diatom cell wall component.

It is demonstrated that EDTA treatment removes most of the proteins present in mature cell walls of the marine diatom Cylindrotheca fusiformis, indicating that these proteins represent a new family of proteins that are involved in the biogenesis of diatom cell walls.


Evidence that organic material exists within diatom biosilica and can be extracted using HF/NH4F solutions from frustules isolated from Cyclotella meneghiniana Kütz and diatomaceous earth is presented and indirect evidence is presented that suggests the soluble proteins may contain regions of primary structure enriched in anionic amino acids.