title: Distinct macroscopic structures developed from solutions of chemical compounds and periodic proteins.
abstract: By controlling the growth of inorganic crystals, macro-biomolecules, including proteins, play pivotal roles in modulating biomineralization. Natural proteins that promote biomineralization are often composed of simple repeats of peptide sequences; however, the relationship between these repetitive structures and their functions remains largely unknown. Here we show that an artificial protein containing a repeated peptide sequence allows NaCl, KCl, CuSO(4) and sucrose to form a variety of macroscopic structures, as represented by their dendritic configurations. Mutational analyses revealed that the physicochemical characteristics of the protein, not the peptide sequence per se, were responsible for formation of the dendritic structures. This suggests that proteins that modulate crystal growth may have evolved as repeat-containing forms at a relatively high rate. These observations could serve as the basis for developing new genetic programming systems for creation of artificial proteins able to modulate crystal growth from inorganic compounds, and may thus provide a new tool for nano-biotechnology.
authors.affiliation: Department of Protein Engineering, Cancer Institute, Japanese Foundation for Cancer Research, Toshima, Tokyo 170-8455, Japan. kshiba@jfcr.or.jp
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Shiba
authors.forename: Takako
authors.initials: T
authors.lastname: Honma
authors.forename: Tamiko
authors.initials: T
authors.lastname: Minamisawa
authors.forename: Keiichi
authors.initials: K
authors.lastname: Nishiguchi
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Noda
mesh_terms: D003460:Crystallization; D004252:DNA Mutational Analysis; D036103:Nanotechnology; D015202:Protein Engineering; D011506:Proteins / Q000378:metabolism*; D012965:Sodium Chloride / Q000378:metabolism*
chemical_list: D011506:Proteins; D012965:Sodium Chloride