Publication Date:
2013-03-16
Description:
Silicatein-alpha is responsible for the biomineralization of silicates in sponges. We used silicatein-alpha to guide the self-assembly of calcite "spicules" similar to the spicules of the calcareous sponge Sycon sp. The self-assembled spicules, 10 to 300 micrometers (mum) in length and 5 to 10 mum in diameter, are composed of aligned calcite nanocrystals. The spicules are initially amorphous but transform into calcite within months, exhibiting unusual growth along [100]. They scatter x-rays like twinned calcite crystals. Whereas natural spicules evidence brittle failure, the synthetic spicules show an elastic response, which greatly enhances bending strength. This remarkable feature is linked to a high protein content. With nano-thermogravimetric analysis, we measured the organic content of a single spicule to be 10 to 16%. In addition, the spicules exhibit waveguiding properties even when they are bent.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Natalio, Filipe -- Corrales, Tomas P -- Panthofer, Martin -- Schollmeyer, Dieter -- Lieberwirth, Ingo -- Muller, Werner E G -- Kappl, Michael -- Butt, Hans-Jurgen -- Tremel, Wolfgang -- New York, N.Y. -- Science. 2013 Mar 15;339(6125):1298-302. doi: 10.1126/science.1216260.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institut fur Anorganische Chemie und Analytische Chemie, Johannes Gutenberg-Universitat, Mainz, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23493708" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Calcium Carbonate/*chemistry
;
Cathepsins/*chemistry
;
Microscopy, Electron, Transmission
;
Nanoparticles/chemistry
;
Porifera
;
Spectroscopy, Fourier Transform Infrared
;
*Stress, Mechanical
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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