Self-assembly of highly phosphorylated silaffins and their function in biosilica morphogenesis

Science. 2002 Oct 18;298(5593):584-6. doi: 10.1126/science.1076221.

Abstract

Silaffins are uniquely modified peptides that have been implicated in the biogenesis of diatom biosilica. A method that avoids the harsh anhydrous hydrogen fluoride treatment commonly used to dissolve biosilica allows the extraction of silaffins in their native state. The native silaffins carry further posttranslational modifications in addition to their polyamine moieties. Each serine residue was phosphorylated, and this high level of phosphorylation is essential for biological activity. The zwitterionic structure of native silaffins enables the formation of supramolecular assemblies. Time-resolved analysis of silica morphogenesis in vitro detected a plastic silaffin-silica phase, which may represent a building material for diatom biosilica.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Wall / chemistry
  • Cell Wall / metabolism
  • Chemical Precipitation
  • Chromatography, High Pressure Liquid
  • Diatoms / chemistry*
  • Diatoms / metabolism
  • Hydrogen-Ion Concentration
  • Magnetic Resonance Spectroscopy
  • Microscopy, Electron, Scanning
  • Molecular Weight
  • Morphogenesis
  • Particle Size
  • Peptides
  • Phosphates / chemistry
  • Phosphorus / analysis
  • Phosphorylation
  • Phosphoserine / chemistry
  • Polyamines / chemistry
  • Proteins / chemistry*
  • Proteins / isolation & purification*
  • Proteins / metabolism
  • Silicon Dioxide / chemistry*
  • Silicon Dioxide / metabolism
  • Spectrometry, Mass, Electrospray Ionization
  • Static Electricity

Substances

  • Peptides
  • Phosphates
  • Polyamines
  • Proteins
  • silaffin 1A
  • Phosphoserine
  • Phosphorus
  • Silicon Dioxide