Self-assembling light-harvesting systems from synthetically modified tobacco mosaic virus coat proteins.
ABSTRACT A new protein-based approach has been developed for the construction of light-harvesting systems through self-assembly. The building blocks were prepared by attaching fluorescent chromophores to cysteine residues introduced on tobacco mosaic virus coat protein monomers. When placed under the appropriate buffer conditions, these conjugates could be assembled into stacks of disks or into rods that reached hundreds of nanometers in length. Characterization of the system using fluorescence spectroscopy indicated that efficient energy transfer could be achieved from large numbers of donor chromophores to a single acceptor. Energy transfer is proposed to occur through direct donor-acceptor interactions, although degenerate donor-to-donor transfer events are also possible. Three-chromophore systems were also prepared to achieve broad spectrum light collection with over 90% overall efficiency. Through the combination of self-organizing biological structures and synthetic building blocks, a highly tunable new method has emerged for the construction of photovoltaic device components.
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ABSTRACT: The electrons transfer (ET) from an atom or a molecule, donor (D), to another, acceptor (A) is the basis of many fundamental chemical and physical processes. The ET mechanism is controlled by spatial arrangements of donor and acceptors: it's the particular spatial arrangement and thus the particular distance and the orientation between the electron donors and acceptors that controls the efficiency in charge separation processes in nature. Here, we stress the importance of this concept reviewing how spatial distribution of atomic and molecular self-assembly can determine the quality and physical features of ET process from biology to material science. In this context, we propose novel lab-on-chip techniques to be used to control spatial distribution of molecules at nanoscale. Synchrotron source brightness jointly to focusing optics fabrication allows one nowadays to monitor and visualize structures with sub-micrometric spatial resolution. This can give us a new powerful tool to set up sophisticated X-ray imaging techniques as well as spectroscopic elemental and chemical mapping to investigate the structure-function relationship controlling the spatial arrangement of the molecules at nanoscale. Finally, we report intriguing recent case studies on the possibility to manipulate and control this spatial distribution and material functionality at nanoscale by using X ray illumination.Current Protein and Peptide Science 03/2014; · 2.33 Impact Factor
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ABSTRACT: M13 bacteriophage (phage) has emerged as an attractive bionanomaterial owing to its genetically tunable surface chemistry and its potential to self-assemble into hierarchical structures. Furthermore, because of its unique nanoscopic structure, phage has been proposed as a model system in soft condensed physics and as a biomimetic building block for structured functional materials. Genetic engineering of phage provides great opportunities to develop novel nanomaterials with functional surface peptide motifs; however, this biological approach is generally limited to peptides containing the 20 natural amino acids. To extend the scope of phage applications, strategies involving chemical modification have been employed to incorporate a wider range of functional groups, including synthetic chemical compounds. In this review, we introduce the design of chemoselective phage functionalization and discuss how such a strategy is combined with genetic engineering for a variety of medical applications, as reported in recent literature.International Journal of Nanomedicine 01/2014; 9:5825-5836. · 4.20 Impact Factor
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ABSTRACT: As biological agents, viruses come in an astounding range of sizes, with varied shapes and surface morphologies. The structures of viral capsids are generally assemblies of hundreds of copies of one or a few proteins which can be harnessed for use in a wide variety of applications in biotechnology, nanotechnology, and medicine. Despite their complexity, many capsid types form as homogenous populations of precise geometrical assemblies. This is important in both medicine, where well-defined therapeutics are critical for drug performance and federal approval, and nanotechnology, where precise placement affects the properties of the desired material. Here we review the production of viruses and virus-like particles with methods for selecting and manipulating the size, surface chemistry, assembly state, and interior cargo of capsid. We then discuss many of the applications used in research today and the potential commercial and therapeutic products from engineered viral capsids.Applied Microbiology and Biotechnology 05/2014; · 3.81 Impact Factor