title: Fibrous and helical calcite crystals induced by synthetic polypeptides containing o-phospho-L-serine and o-phospho-L-threonine.
abstract: The modification of CaCO(3) crystal growth by synthetic L-Ser(PO(3)H(2)) and L-Thr(PO(3)H(2)) containing polypeptides is described. The amino acids Gly, L-Glu, L-Asp, L-Ser, L-Ala, and L-Lys induced rhombohedral calcite with a rough surface. Dipeptides, Xaa-L-Ser(PO(3)H(2)) (Xaa = Gly, L-Glu, L-Asp, L-Ser, L-Ala and L-Lys) induced vaterite crystals in the lower [Ca(2+)]. On the other hand, L-Ser(PO(3)H(2))-containing polypeptides formed spherical vaterite and fibrous calcite. The characteristic helical calcite was found in the presence of copoly[L-Ser(PO(3)H(2))(75)L-Asp(25)] or poly[L-Ser(PO(3)H(2))(3)-L-Asp]. Fibrous calcite, spherical vaterite, and helical calcite crystals were subjected to XRD and EDX analysis. XRD revealed the specific faces of these crystals. EDX spectra and surface analysis visualized the localization of the polypeptides and CaCO(3) components. Together with TEM and SAED data, we propose hypothetical growth mechanisms for the fibrous and helical calcite crystals.
authors: Institute of High Polymer Research, Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Nagano Prefecture, Japan. hyihpr2@giptc.shinshu-u.ac.jp
authors: Shinya
authors: S
authors: Hayashi
authors: Kousaku
authors: K
authors: Ohkawa
authors: Yukie
authors: Y
authors: Suwa
authors: Tetsunori
authors: T
authors: Sugawara
authors: Takahiro
authors: T
authors: Asami
authors: Hiroyuki
authors: H
authors: Yamamoto
mesh_terms: D002119:Calcium Carbonate / Q000138:chemical synthesis / Q000737:chemistry*; D003460:Crystallization; D008854:Microscopy, Electron; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D010768:Phosphoserine / Q000737:chemistry*; D010769:Phosphothreonine / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D010455:Peptides; D010769:Phosphothreonine; D010768:Phosphoserine; D002119:Calcium Carbonate