title: Coordination-driven folding and assembly of a short peptide into a protein-like two-nanometer-sized channel.
abstract: Short peptide helices have attracted attention as suitable building blocks for soft functional materials, but they are rarely seen in crystalline materials. A new artificial nanoassembly of short peptide helices in the crystalline state is presented in which peptide helices are arranged three-dimensionally by metal coordination. The folding and assembly processes of a short peptide ligand containing the Gly-Pro-Pro sequence were induced by silver(I) coordination in aqueous alcohol, and gave rise to a single crystal composed of polyproline II helices. Crystallographic studies revealed that this material possesses two types of unique helical nanochannel; the larger channel measures more than 2 nm in diameter. Guest uptake properties were investigated by soaking the crystals in polar solutions of guest molecules; anions, organic chiral molecules, and bio-oligomers are effectively encapsulated by this peptide-folded porous crystal, with moderate to high chiral recognition for chiral molecules.
authors.affiliation: Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan). tsawada@appchem.t.u-tokyo.ac.jp.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Sawada
authors.forename: Asami
authors.initials: A
authors.lastname: Matsumoto
authors.forename: Makoto
authors.initials: M
authors.lastname: Fujita
mesh_terms: D002214:Capsules; D056831:Coordination Complexes / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D043942:Nanotubes / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D017510:Protein Folding; D017433:Protein Structure, Secondary; D012834:Silver / Q000737:chemistry*
chemical_list: D002214:Capsules; D056831:Coordination Complexes; D010455:Peptides; D012834:Silver
keywords: chiral recognition; coordination; molecular recognition; peptide folding; self-assembly