Springer protocols feed by Biotechnology 
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This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.Engineered Bacteriophage T4 Nanoparticles for Cellular Imaging
Tailless T4 nanoparticles (NPs) have large surface areas consisting of more than 105 diverse surface reactive groups and offer great flexibility in chemical modification for tailoring the desired functionality. Dye-conjugated T4 NPs exhibiting bright fluorescence are biocompatible and can be internalized by various eukaryotic cells which land themselves as excellent cellular imaging agents. Here, we describe the preparation of engineered T4 NPs including dye-conjugation and characterization, and the procedure for cellular uptake and confocal microscopy. (Source: Springer protocols feed by Biotechnology)
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Chemical Modification of the Inner and Outer Surfaces of Tobacco Mosaic Virus (TMV)
We report the purification and chemical modification of TMV which is a hollow rod-shaped plant viral nanoparticle with modifiable interior and exterior surfaces. We describe methods to isolate TMV from its tobacco plant host for spatially controlled interior and exterior chemical modification and to characterize the resulting TMV hybrid materials. (Source: Springer protocols feed by Biotechnology)
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
A Programmable Fluorescent Viral Nanoblock: Sensing Made Easy in a Single Step
Viral nanoblock provides specific positioning of recognition moieties and dye molecules which can be used as a signal-generating element and enhance detection sensitivity. The methods described herein use a 30 nm viral nanoblock to couple a variety of proteins and peptides for the incorporation of recognition elements along with a large number of dye molecules (200). The bioconjugation techniques were adapted and optimized over the years to fabricate nanoparticles that exhibit high fluorescence output while maintaining the selectivity of the target receptors. These complexes can be used for the detection of pathogens and t...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Genetic Engineering and Characterization of Cowpea Mosaic Virus Empty Virus-Like Particles
The development of methods for the production of empty Cowpea mosaic virus (CPMV) virus-like particles (VLPs) that are devoid of RNA, eVLPs, has renewed promise in CPMV capsid technologies. The recombinant nature of CPMV eVLP production means that the extent and variety of genetic modifications that may be incorporated into the particles is theoretically much greater than those that can be made to infectious CPMV virions due to restrictions on viral propagation of the latter. Free of the infectious agent, the genomic RNA, these particles are now finding potential uses in vaccine development, in vivo imaging, drug delivery,...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Tobacco Mosaic Virus Assembled High Aspect Ratio Surfaces
A modified version of the rod-shaped Tobacco Mosaic Virus (TMV1cys) provides a robust template for the self-assembly and fabrication of high-surface-area materials for numerous applications including batteries and sensors. TMV1cys surface fabrication is facilitated by the addition of a single cysteine residue to the virus coat protein that directs the vertical attachment of the virus particle onto substrate surfaces and enables deposition of functional inorganic layers. Here we describe the production and purification of the virus, its assembly onto suitable surfaces, and coating with metallic nickel and cobalt. (Source: S...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Tobacco Mosaic Virus Capsid Protein as Targets for the Self-Assembly of Gold Nanoparticles
Bottom-up self-assembly techniques are a powerful method of building nanoscale structures in an energy efficient and cost effective manner. The use of biological templates, such as proteins, takes advantage of the monodispersity and precision of naturally evolved systems to produce highly organized assemblies of small molecules and nanoparticles. Here we describe a method whereby arginine residues on a viral coat protein (Tobacco Mosaic Virus) are targeted by bis(p-sulfonatophenyl)phenylphosphine (BSPP)-passivated gold nanoparticles with high specificity to create 22 nm rings. (Source: Springer protocols feed by Biotechnology)
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Polyelectrolyte-Modified Cowpea Mosaic Virus for the Synthesis of Gold Nanoparticles
Polyelectrolyte surface-modified cowpea mosaic virus (CPMV) can be used for the templated synthesis of narrowly dispersed gold nanoparticles. Cationic polyelectrolyte, poly(allylamine) hydrochloride, is electrostatically bound to the external surface of the virus capsid. The polyelectrolyte-coated CPMV promotes adsorption of aqueous gold hydroxide anionic species, prepared from gold(III) chloride and potassium carbonate, that are easily reduced to form CPMV-templated gold nanoparticles. The process is simple and environmentally benign using only water as solvent at ambient temperature. (Source: Springer protocols feed by Biotechnology)
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Templated Mineralization by Charge-Modified Cowpea Mosaic Virus
Templated mineralization of virus particles provides routes to narrowly dispersed nanoparticles that are not readily prepared by other means. The templated mineralization of metal or metal oxide on the external surface of wild-type cowpea mosaic virus (CPMV), a plant virus, is facilitated by increasing the external surface negative charge. This is achieved by the chemical modification of surface lysine groups by succinic anhydride. Hence, for example, treatment of charge-modified CPMV succinamate with a 1:2 mixture of iron(II) and iron(III) salts, followed by raising the pH to 10.2, led to the formation of narrowly dispers...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Phage as a Template to Grow Bone Mineral Nanocrystals
Phage display is a biotechnique that fuses functional peptides on the outer surface of filamentous phage by inserting DNA encoding the peptides into the genes of its coat proteins. The resultant peptide-displayed phage particles have been widely used as biotemplates for the synthesis of functional hybrid nanomaterials. Here, we describe the bioengineering of M13 filamentous phage to surface-display bone mineral (hydroxyapatite (HAP))-nucleating peptides derived from dentin matrix protein-1 and using the engineered phage as a biotemplate to grow HAP nanocrystals. (Source: Springer protocols feed by Biotechnology)
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Bacteriophage T4 Capsid Packaging and Unpackaging of DNA and Proteins
Bacteriophage T4 has proven itself readily amenable to phage-based DNA and protein packaging, expression, and display systems due to its physical resiliency and genomic flexibility. As a large dsDNA phage with dispensable internal proteins and dispensable outer capsid proteins it can be adapted to package both DNA and proteins of interest within the capsid and to display peptides and proteins externally on the capsid. A single 170 kb linear DNA, or single or multiple copies of shorter linear DNAs, of any sequence can be packaged by the large terminase subunit in vitro into protein-containing proheads and give full or parti...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Using Phage as a Platform to Select Cancer Cell-Targeting Peptides
One challenge in the development of cancer therapies is the availability of cancer-specific ligands. Recently, phage-displayed peptide libraries have been used for the selection of peptide-based cell-targeting ligands, especially cancer cell ligands. Here we describe the methods to identify SKBR-3 breast cancer cell-specific peptides from a phage-displayed random peptide library. It is possible to select both cell-surface-binding and cell-internalizing peptides using this method. This method can also be applied to the selection of targeting peptides for other adherent cancer cells. The identified short peptides can be pote...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Simulated Digestion for Testing the Stability of Edible Vaccine Based on Cucumber mosaic virus (CMV) Chimeric Particle Display Hepatitis C virus (HCV) Peptide
Edible vaccines must survive digestive process and preserve the specific structure of the antigenic peptide to elicit effective immune response. The stability of a protein to digestive process can be predicted by subjecting it to the in vitro assay with simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). Here, we describe the protocol of producing and using chimeric Cucumber mosaic virus (CMV) displaying Hepatitis C virus (HCV) derived peptide (R9) in double copy as an oral vaccine. Its stability after treatment with SGF and SIF and the preservation of the antigenic properties were verified by SDS-PAGE and ...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Genetically Engineering Adenoviral Vectors for Gene Therapy
Adenoviral (Ad) vectors are commonly used for various gene therapy applications. Significant advances in the genetic engineering of Ad vectors in recent years has highlighted their potential for the treatment of metastatic disease. There are several methods to genetically modify the Ad genome to incorporate retargeting peptides which will redirect the natural tropism of the viruses, including homologous recombination in bacteria or yeast. However, homologous recombination in yeast is highly efficient and can be achieved without the need for extensive cloning strategies. In addition, the method does not rely on the presence...
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
Genetic Engineering and Chemical Conjugation of Potato Virus X
We present three methods of chemical bioconjugation. For direct conjugation of small chemical modifiers to solvent exposed lysines, N-hydroxysuccinimide chemistry can be applied. Bio-orthogonal reactions such as copper-catalyzed azide–alkyne cycloaddition or hydrazone ligation are alternatives to achieve more efficient conjugation (e.g., when working with high molecular weight or insoluble ligands). Furthermore, hydrazone ligation offers an attractive route for the introduction of pH-cleavable cargos (e.g., therapeutic molecules). (Source: Springer protocols feed by Biotechnology)
Source: Springer protocols feed by Biotechnology - November 20, 2013 Category: Biotechnology Source Type: news
A Method to Map Spatiotemporal pH Changes in a Multicellular Living Organism Using a DNA Nanosensor
Environmental pH has a determining role in the structure of biomolecules, thus playing an important role in regulating cellular activities. Eukaryotic cells must, therefore, strive to stringently regulate pH in various intracellular organelles so as to confer normal functioning at the level of whole organism. Several pH-sensitive probes have been reported, each of which can be used to map the pH dependence of an in vivo process. However, these probes suffer from some inherent drawbacks. Here we demonstrate the utility of an externally introduced, pH-triggered DNA nanomachine inside the multicellular eukaryote Caenorhabditi...
Source: Springer protocols feed by Biotechnology - April 11, 2013 Category: Biotechnology Source Type: news
