title: Supramolecular amplification of amyloid self-assembly by iodination.
abstract: Amyloid supramolecular assemblies have found widespread exploitation as ordered nanomaterials in a range of applications from materials science to biotechnology. New strategies are, however, required for understanding and promoting mature fibril formation from simple monomer motifs through easy and scalable processes. Noncovalent interactions are key to forming and holding the amyloid structure together. On the other hand, the halogen bond has never been used purposefully to achieve control over amyloid self-assembly. Here we show that single atom replacement of hydrogen with iodine, a halogen-bond donor, in the human calcitonin-derived amyloidogenic fragment DFNKF results in a super-gelator peptide, which forms a strong and shape-persistent hydrogel at 30-fold lower concentration than the wild-type pentapeptide. This is remarkable for such a modest perturbation in structure. Iodination of aromatic amino acids may thus develop as a general strategy for the design of new hydrogels from unprotected peptides and without using organic solvents.
authors.affiliation: Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering 'Giulio Natta', Politecnico di Milano, Via Mancinelli 7, Milano I-20131, Italy.
authors.forename: Arianna
authors.initials: A
authors.lastname: Bertolani
authors.affiliation: 1] Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering 'Giulio Natta', Politecnico di Milano, Via Mancinelli 7, Milano I-20131, Italy [2] VTT-Technical Research Centre of Finland, PO Box 1000, Espoo FI-02044, Finland.
authors.forename: Lisa
authors.initials: L
authors.lastname: Pirrie
authors.affiliation: Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering 'Giulio Natta', Politecnico di Milano, Via Mancinelli 7, Milano I-20131, Italy.
authors.forename: Loic
authors.initials: L
authors.lastname: Stefan
authors.affiliation: Department of Applied Physics, Aalto University, PO Box 15100, Espoo FI-02150, Finland.
authors.forename: Nikolay
authors.initials: N
authors.lastname: Houbenov
authors.affiliation: Department of Applied Physics, Aalto University, PO Box 15100, Espoo FI-02150, Finland.
authors.forename: Johannes S
authors.initials: JS
authors.lastname: Haataja
authors.affiliation: Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering 'Giulio Natta', Politecnico di Milano, Via Mancinelli 7, Milano I-20131, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Catalano
authors.affiliation: Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering 'Giulio Natta', Politecnico di Milano, Via Mancinelli 7, Milano I-20131, Italy.
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Terraneo
authors.affiliation: Dipartimento Beni Culturali, Università del Salento, Lecce I-73100, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Giancane
authors.affiliation: Dipartimento Beni Culturali, Università del Salento, Lecce I-73100, Italy.
authors.forename: Ludovico
authors.initials: L
authors.lastname: Valli
authors.affiliation: VTT-Technical Research Centre of Finland, PO Box 1000, Espoo FI-02044, Finland.
authors.forename: Roberto
authors.identifier: 0000000279977847
authors.initials: R
authors.lastname: Milani
authors.affiliation: Department of Applied Physics, Aalto University, PO Box 15100, Espoo FI-02150, Finland.
authors.forename: Olli
authors.initials: O
authors.lastname: Ikkala
authors.affiliation: Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering 'Giulio Natta', Politecnico di Milano, Via Mancinelli 7, Milano I-20131, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Resnati
authors.affiliation: 1] Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering 'Giulio Natta', Politecnico di Milano, Via Mancinelli 7, Milano I-20131, Italy [2] VTT-Technical Research Centre of Finland, PO Box 1000, Espoo FI-02044, Finland.
authors.forename: Pierangelo
authors.initials: P
authors.lastname: Metrangolo
mesh_terms: D000682:Amyloid / Q000737:chemistry*; D002942:Circular Dichroism; D055032:Electron Microscope Tomography; D054879:Halogenation; D006358:Hot Temperature; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D010649:Phenylalanine / Q000031:analogs & derivatives; D011487:Protein Conformation; D055550:Protein Stability; D012212:Rheology
chemical_list: D000682:Amyloid; D010649:Phenylalanine