Modified Filamentous Bacteriophage as a Scaffold for Carbon Nanofiber

Abstract

With the advent of nanotechnology, carbon nanomaterials such as carbon nanofibers (CNF) have aroused substantial interest in various research fields including energy storage and sensing. Further improvement of their properties might be achieved via application of viral particles such as bacteriophages. In this report we present a filamentous M13 bacteriophage, with a point mutation in gene VII (pVII-mutant-M13), that selectively binds to the carbon nanofibers to form 3D structures. The phage-display technique was utilized for the selection of the pVII-mutant-M13 phage from the phage display peptide library. The properties of this phage make it a prospective candidate for a scaffold material for CNFs. The results for binding of CNF by mutant phage were compared with those for maternal bacteriophage (pVII-M13). The efficiency of binding between pVII-mutant-M13 and CNF is about two orders of magnitude higher compared to the pVII-M13. Binding affinity between the pVII-mutant-M13 and CNF was also characterized using atomic force microscopy, scanning electron microscopy and transmission electron microscopy, which confirmed the specificity of the interaction of the phage pVII-mutant-M13 and the CNF - the binding occurs via phage's ending where the mutated pVII protein is located. No similar behaviour has been observed for other carbon nanomaterials such as: graphite, reduced graphene oxide, single-walled carbon nanotubes and multi-walled carbon nanotubes. Infrared spectra confirmed differences in the interaction with CNF between the pVII-mutant-M13 and pVII-M13. Basing on conducted research we hypothesize that the interactions are non-covalent in nature, with π-π interactions playing the dominant role. Herein the new bioconjugate material is introduced