Silica-containing inclusions in the cytoplasm of diatom Synedra acus

Abstract

Cells of the araphid pennate diatom Synedra acus subsp. radians contain large inclusion (1-15 μm) storing silica, as revealed by transmission electron microscopy and EDX-analysis. The size of the inclusions increases with the time of cultivation of diatoms. Approximate concentration of SiO in the inclusions is 1-4%. It is assumed that silica in the inclusions is present as gelatinized silica-gel. These results explain the possible mechanism of transport of silicic acid into the cell against the concentration gradient.

Porous cellulose microspheres loaded with dry Nile water algae for removal of MB dye and copper ions from aqueous media

“…The presence of silica components in EDX and FT‐IR data is clear evidence of the occurrence of diatoms (group of algae) that is characterized by a silica cell wall. [ 29,73 ]…”

“…The presence of silica components in EDX and FT-IR data is clear evidence of the occurrence of diatoms (group of algae) that is characterized by a silica cell wall. [29,73] 3.2 | Evaluation of the optimum condition for dyes and metal removal At 60 min, the effectiveness of MB and Cu (II) adsorption had increased to 81, 79, and 67.5% for 20 mg/L of MB and 10 and 20 mg/L of Cu (II), respectively. However, no further adsorption occurs after 60 min.…”

A review on diatom biosilicification and their adaptive ability to uptake other metals into their frustules for potential application in bone repair

“…35,36 Grachev et al work on the same pennate shaped diatom species, Synedra acus, supports Annenkov findings. 37 Martin-Jézéquel et al acknowledges polymerisation in the cytoplasm but suggests it is the result of an uncontrolled autopolymerisation that can occur when not enough silicon is transported to the SDV. 19 Vrieling et al suggests that silicic uptake in the vicinity of the SDV is more likely also to prevent autopolymerisation, otherwise stabilisation of the silicic acid and/or precursors would be required.…”

A New View into the Silica Deposition Vesicles of Diatoms

“…In T. pseudonana, the nanoparticles were only observed during cribrum pore formation and were primarily associated with the costae. It has previously been hypothesized that silica nanoparticles are the primary building blocks for biosilica morphogenesis inside the SDV (24,30,(44)(45)(46)(47). The hypothesis was based on rather circumstantial evidence, and previous methods for SDV imaging failed to demonstrate the presence of such aggregates inside SDVs.…”