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"BIOSILIFICATION in diatoms and sponges has been facilitated by small peptides – silafins and silicatein respectively at the molecular level. However, few other peptides such as frustulins and pleurolins have been identified to play a crucial role in the formation of biosilica. Silafins and silicateins isolated from diatoms cell wall and sponge spicules are demonstrated to induce in vitro formation of silica by hydrolyzing silicic acid or tetra ethoxy orthosilane." https://lnkd.in/es5DATt View in LinkedIn

NOTHING TOO SMALL. No aspect of nature is too insignificant to deserve the durable intellectual attentions of curious people. Be it butterfly wing scales, chirality, feather coloration, or the beauties of microscopic marine shells. Centuries of careful scholarship of natural systems deepen our appreciation and connection to the natural world. View in LinkedIn

MOLECULAR UNKNOWNS. "While the morphology and ultrastructure of silica deposition have been described in detail for a number of diatom species, little is known about the mechanisms of deposition at the molecular level. In an analogous way to coccolithophorid calcification." https://lnkd.in/eXTtntg View in LinkedIn

SO ENDS this section on biomineralization by tiny marine creatures. Impressive scholarship has gone a long way to understanding the rule-breaking geometry and strange biomineralization chemistry; and to understanding the minimal surface energetics and bioenergetics in terms of ATP costs. Much more remains to be discovered. No aspect of nature is too insignificant to deserve the durable intellectual attentions of curious people. Be it butterfly wing scales, feather coloration, or the beauties of microscopic shells. View in LinkedIn

CRYSTAL GROWTH. "Regulation of calcite growth by coccolithophores is almost as remarkable as the regulation of nucleation. The crystal units...are each single crystals of calcite, and their shapes are radically different from that of inorganic calcite. However, such crystals do not exist in isolation, but are parts of the complete coccolith, and much of the morphology is a product of interaction between adjacent crystals." https://lnkd.in/eUUB9pU View in LinkedIn

GENETICS. "Recent progress has been made in the cloning and functional expression of cDNAs coding diatom silicic acid transporters." https://lnkd.in/eXTtntg View in LinkedIn

CO2 AND RUBISCO. "In the marine environment, CO2 is present in micromolar concentrations, which may be lower than the dissociation constant (Km) for the photosynthetic carbon-fixing enzyme ribulose bisphosphate carboxylase oxygenase (Rubisco). Phytoplankton species that rely on CO2 diffusion to supply photosynthesis may be rate-limited by the CO2 concentration and diffusion to the site of Rubisco in the chloroplast." https://lnkd.in/eXTtntg View in LinkedIn

SUPERSATURATION. "The most striking feature of calcification in the oceans is that it occurs almost exclusively by biogenic processes. Ca2 and CO2 inputs into the oceans occur through weathering of rocks, geothermal activity and hydrothermal seepage. The ocean is in fact supersaturated with Ca2 and CO2. However, spontaneous chemical precipitation is largely absent owing to the high concentrations of inhibitory ions in seawater and the presence of crystal poisons produced by the biota." https://lnkd.in/eXTtntg View in LinkedIn

SUPERSATURATION. "The most striking feature of calcification in the oceans is that it occurs almost exclusively by biogenic processes. Ca2 and CO2 inputs into the oceans occur through weathering of rocks, geothermal activity and hydrothermal seepage. The ocean is in fact supersaturated with Ca2 and CO2. However, spontaneous chemical precipitation is largely absent owing to the high concentrations of inhibitory ions in seawater and the presence of crystal poisons produced by the biota." https://lnkd.in/eXTtntg View in LinkedIn

WORTH REPEATING. "Until recently, only the protein-coding regions of DNA was thought to be crucial to coding. While this may well be the case in the prokaryotes, in higher eukaryotes this region is marginal (3%), for 97% of the eukaryotic genome consists of non-coding DNA." https://lnkd.in/eDswHmC View in LinkedIn