from ScrippsInstitutionOfOceanographyNews Website
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Diatoms, tiny single-celled plants
that cover much of the world's oceans, come in a variety of
beautiful and sometimes odd-looking shapes. Made of
silicon, their rigid cell walls can
resemble everything from pillboxes to pinwheels.
The researchers reported their finding in the February 20 issue of the journal Nature.
Silicon is essential in biological systems, affecting development and cellular metabolism. It is second only to oxygen in abundance and is widely distributed on the Earth's surface. Diatoms take up silicon in the form of silicic acid from the surrounding ocean, transport it across their cell membrane and use it to build structures that have chemical and physical characteristics similar to glass.
While the diatom provides a perfect model for studying silicon transport, Hildebrand said the information learned also may be applied to mammals, including humans.
Scientists estimate there are more than 10,000 species of diatoms, each characterized on the basis of their shape, which is handed down from generation to generation. Because diatoms are so tiny - ranging between 10 and 20 microns in size - Hildebrand said new information on how they reproduce their structures could be applied to the manufacture of nano-structured materials.
These novel materials, which measure only a few nanometers in size, are being explored for uses such as nanofabrication, making devices on an extremely small scale.
Hildebrand said continued work using advanced molecular genetic techniques should allow he and his colleagues to discover the underlying mechanism that allows silicon to be transported into different compartments within the cell.
They also hope to learn how silicon
transport across the cell membrane is regulated.