Peptide Induced Crystallization of Calcium Carbonate on Wrinkle Patterned Substrate: Implications for Chitin Formation in Molluscs

International Journal of Molecular Sciences

Anindita Sengupta Ghatak²  Marcus Koch¹  Christina Guth² 

[1] Program Division “Innovative Electron Microscopy”, INM—Leibniz Institute for New Materials gGmbH, D-66123 Saarbruecken, Germany; E-Mail:;Program Division “Biomineralization”, INM—Leibniz Institute for New Materials gGmbH, D-66123 Saarbruecken, Germany; E-Mail:

关键词: wrinkle substrate;    peptide;    crystal;    pH;    composites;    chitin synthase;    mollusc shell;   

DOI  :  10.3390/ijms140611842

来源: mdpi

【 摘 要 】

We here present the nucleation and growth of calcium carbonate under the influence of synthetic peptides on topographically patterned poly(dimethylsiloxane) (PDMS) substrates, which have a controlled density of defects between the wrinkles. Experiments with two lysine-rich peptides derived from the extracellular conserved domain E22 of the mollusc chitin synthase Ar-CS1, AKKKKKAS (AS8) and EEKKKKKES (ES9) on these substrates showed their influence on the calcium carbonate morphology. A transition from polycrystalline composites to single crystalline phases was achieved with the peptide AS8 by changing the pH of the buffer solution. We analyzed three different pH values as previous experiments showed that E22 interacts with aragonite biominerals more strongly at pH 7.75 than at pH 9.0. At any given pH, crystals appeared in characteristic morphologies only on wrinkled substrates, and did not occur on the flat, wrinkle-free PDMS substrate. These results suggest that these wrinkled substrates could be useful for controlling the morphologies of other mineral/peptide and mineral/protein composites. In nature, these templates are formed enzymatically by glycosyltransferases containing pH-sensitive epitopes, similar to the peptides investigated here. Our in vitro test systems may be useful to gain understanding of the formation of distinct 3D morphologies in mollusc shells in response to local pH shifts during the mineralization of organic templates.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland