title: Heterogeneous distribution of dye-labelled biomineralizaiton proteins in calcite crystals.
abstract: Biominerals are highly ordered crystals mediated by organic matters especially proteins in organisms. However, how specific proteins are distributed inside biominerals are not well understood. In the present study, we use fluorescein isothiocyanate (FITC) to label extracted proteins from the shells of bivalve Pinctada fucata. By confocal laser scanning microscopy (CLSM), we observe a heterogeneous distribution of dye-labelled proteins inside synthetic calcite at the microscale. Proteins from the prismatic calcite layers accumulate at the edge of crystals while proteins from the nacreous aragonite layers accumulate at the center of crystals. Raman and X-ray powder diffraction show that both the proteins cannot alter the crystal phase. Scanning electron microscope demonstrates both proteins are able to affect the crystal morphology. This study may provide a direct approach for the visualization of protein distributions in crystals by small-molecule dye-labelled proteins as the additives in the crystallization process and improve our understanding of intracrystalline proteins distribution in biogenic calcites.
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing 100084 China.|Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084 China.
authors.forename: Chuang
authors.initials: C
authors.lastname: Liu
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing 100084 China.
authors.forename: Liping
authors.initials: L
authors.lastname: Xie
authors.affiliation: Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing 100084 China.
authors.forename: Rongqing
authors.initials: R
authors.lastname: Zhang
mesh_terms: D060105:Animal Shells / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D000818:Animals; D002119:Calcium Carbonate / Q000737:chemistry / Q000378:metabolism*; D002942:Circular Dichroism; D003460:Crystallization; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D008903:Minerals / Q000378:metabolism*; D060734:Nacre / Q000737:chemistry / Q000378:metabolism; D049911:Pinctada / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D013059:Spectrum Analysis, Raman; D014961:X-Ray Diffraction
chemical_list: D005456:Fluorescent Dyes; D008903:Minerals; D060734:Nacre; D011506:Proteins; D002119:Calcium Carbonate; D016650:Fluorescein-5-isothiocyanate