title: Self-assembly of highly phosphorylated silaffins and their function in biosilica morphogenesis.
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.
authors.affiliation: Lehrstuhl Biochemie I, Institut für Biophysik und Physikalische Biochemie, Universität Regensburg, 93053 Regensburg, Germany.
authors.forename: Nils
authors.initials: N
authors.lastname: Kröger
authors.forename: Sonja
authors.initials: S
authors.lastname: Lorenz
authors.forename: Eike
authors.initials: E
authors.lastname: Brunner
authors.forename: Manfred
authors.initials: M
authors.lastname: Sumper
mesh_terms: D002473:Cell Wall / Q000737:chemistry / Q000378:metabolism; D011232:Chemical Precipitation; D002851:Chromatography, High Pressure Liquid; D017377:Diatoms / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D009024:Morphogenesis; D010316:Particle Size; D010455:Peptides; D010710:Phosphates / Q000737:chemistry; D010758:Phosphorus / Q000032:analysis; D010766:Phosphorylation; D010768:Phosphoserine / Q000737:chemistry; D011073:Polyamines / Q000737:chemistry; D011506:Proteins / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D012822:Silicon Dioxide / Q000737:chemistry* / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D055672:Static Electricity
chemical_list: D010455:Peptides; D010710:Phosphates; D011073:Polyamines; D011506:Proteins; C400535:silaffin 1A; D010768:Phosphoserine; D010758:Phosphorus; D012822:Silicon Dioxide