title: Selection of peptides binding to metallic borides by screening M13 phage display libraries.
abstract: BACKGROUND
  Metal borides are a class of inorganic solids that is much less known and investigated than for example metal oxides or intermetallics. At the same time it is a highly versatile and interesting class of compounds in terms of physical and chemical properties, like semiconductivity, ferromagnetism, or catalytic activity. This makes these substances attractive for the generation of new materials. Very little is known about the interaction between organic materials and borides. To generate nanostructured and composite materials which consist of metal borides and organic modifiers it is necessary to develop new synthetic strategies. Phage peptide display libraries are commonly used to select peptides that bind specifically to metals, metal oxides, and semiconductors. Further, these binding peptides can serve as templates to control the nucleation and growth of inorganic nanoparticles. Additionally, the combination of two different binding motifs into a single bifunctional phage could be useful for the generation of new composite materials.
  
  
  RESULTS
  In this study, we have identified a unique set of sequences that bind to amorphous and crystalline nickel boride (Ni3B) nanoparticles, from a random peptide library using the phage display technique. Using this technique, strong binders were identified that are selective for nickel boride. Sequence analysis of the peptides revealed that the sequences exhibit similar, yet subtle different patterns of amino acid usage. Although a predominant binding motif was not observed, certain charged amino acids emerged as essential in specific binding to both substrates. The 7-mer peptide sequence LGFREKE, isolated on amorphous Ni3B emerged as the best binder for both substrates. Fluorescence microscopy and atomic force microscopy confirmed the specific binding affinity of LGFREKE expressing phage to amorphous and crystalline Ni3B nanoparticles.
  
  
  CONCLUSIONS
  This study is, to our knowledge, the first to identify peptides that bind specifically to amorphous and to crystalline Ni3B nanoparticles. We think that the identified strong binding sequences described here could potentially serve for the utilisation of M13 phage as a viable alternative to other methods to create tailor-made boride composite materials or new catalytic surfaces by a biologically driven nano-assembly synthesis and structuring.
authors: Martin
authors: M
authors: Ploss
authors: Sandra J
authors: SJ
authors: Facey
authors: Carina
authors: C
authors: Bruhn
authors: Limor
authors: L
authors: Zemel
authors: Kathrin
authors: K
authors: Hofmann
authors: Robert W
authors: RW
authors: Stark
authors: Barbara
authors: B
authors: Albert
authors: Institute of Technical Biochemistry, University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany. bernhard.hauer@itb.uni-stuttgart.de.
authors: Bernhard
authors: B
authors: Hauer
mesh_terms: D000595:Amino Acid Sequence; D017104:Bacteriophage M13 / Q000378:metabolism; D001667:Binding, Competitive; D001896:Boron Compounds / Q000737:chemistry*; D008670:Metals / Q000737:chemistry; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D053758:Nanoparticles / Q000737:chemistry; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry*
chemical_list: D001896:Boron Compounds; D008670:Metals; D019151:Peptide Library; D010455:Peptides