کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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2828965 | 1162774 | 2009 | 9 صفحه PDF | دانلود رایگان |
The skeletons of demosponges, such as Ianthella basta, are known to be a composite material containing organic constituents. Here, we show that a filigree chitin-based scaffold is an integral component of the I. basta skeleton. These chitin-based scaffolds can be isolated from the sponge skeletons using an isolation and purification technique based on treatment with alkaline solutions. Solid-state 13C NMR, Raman, and FT-IR spectroscopies, as well as chitinase digestion, reveal that the isolated material indeed consists of chitin. The morphology of the scaffolds has been determined by light and electron microscopy. It consists of cross-linked chitin fibers approximately 40–100 nm in diameter forming a micro-structured network. The overall shape of this network closely resembles the shape of the integer sponge skeleton. Solid-state 13C NMR spectroscopy was used to characterize the sponge skeleton on a molecular level. The 13C NMR signals of the chitin-based scaffolds are relatively broad, indicating a high amount of disordered chitin, possibly in the form of surface-exposed molecules. X-ray diffraction confirms that the scaffolds isolated from I. basta consist of partially disordered and loosely packed chitin with large surfaces. The spectroscopic signature of these chitin-based scaffolds is closer to that of α-chitin than β-chitin.
Journal: Journal of Structural Biology - Volume 168, Issue 3, December 2009, Pages 539–547