Electrostatic conditions define the 2D self-assembly of tomato bushy stunt viruses on solid surfaces.

Plant viruses which are self-assembled on a substrate are interesting building blocks in nanobiotechnology, in particular, for the creation of 2D ordered structures. In this article, the self-assembly of different genetically modified types of the tomato bushy stunt virus spin-coated on pristine silicon was investigated by scanning force and scanning electron microscopy. Amino acid side chains were integrated in the capsids of the viruses by extending the coat protein with different charged amino acid clusters (tetra-aspartate-hexa-histidine, hexa-aspartate, or tetra-arginine-tags). The influence of the resulting electrostatic forces based on virus-virus and virus-surface interactions on the formation of self-assembled monolayers will be presented and discussed in the context of differences in surface coverage for different pH values. It could be shown that the largest surface coverage can be achieved when there is an attraction between the whole virus and the surface and only a minor repulsion between the viruses at a given pH.

Identification of Highly Specific scFvs against Total Adiponectin for Diagnostic Purposes.

Adiponectin is one of the most abundant adipokines secreted from adipose tissue. It acts as an endogenous insulin sensitizer and plasma concentrations are inversely correlated with obesity and metabolic syndrome. A decrease in plasma adiponectin levels normally indicates increased hormonal activity of the visceral lipid tissue, which is associated with decreased insulin sensitivity. It may therefore be considered a valuable biomarker for elucidating the underlying deteriorations resulting in type 2 diabetes and macrovascular disease. Here we present the use of phage display technology to identify highly specific antibody fragments (scFvs) against adiponectin. The selected scFvs showed highly specific binding to globular and native adiponectin in ELISA tests. By using our phage display technology, we were able to obtain monoclonal antibodies with specific high affinity binding to the target protein in an effective and easy to upscale manner. The selected scFvs against adiponectin can be used for developing immunoassays suitable for use in metabolic syndrome diagnosis and monitoring.

Immunodominant membrane proteins of phytoplasmas.

Phytoplasmas are plant-pathogenic, phloem-colonizing, cell wall-less microorganisms that are primarily dependent on insect transmission for their spread and survival. The life cycle of phytoplasmas involves replication in insects and host plants. Until recently, phytoplasmas have resisted all attempts at cultivation in cell-free media, making these pathogens poorly characterized on a physiological and biochemical basis. However, host-pathogen relationships can be studied by investigating immunodominant membrane proteins (IDPs), which are located on the exterior surfaces of phytoplasma cells and are the most abundant proteins of the cell membrane. These membrane proteins come in direct contact with both insect and plant hosts and are thought to play a crucial role in phytoplasma spread both within the plant and by insect vectors. Therefore, there is great interest in studying this class of proteins. We summarize and discuss important investigations about these membrane proteins, which have already provided a better understanding of the host-phytoplasma relationship.

Reverse Genetics and High Throughput Sequencing Methodologies for Plant Functional Genomics.

In the post-genomic era, increasingly sophisticated genetic tools are being developed with the long-term goal of understanding how the coordinated activity of genes gives rise to a complex organism. With the advent of the next generation sequencing associated with effective computational approaches, wide variety of plant species have been fully sequenced giving a wealth of data sequence information on structure and organization of plant genomes. Since thousands of gene sequences are already known, recently developed functional genomics approaches provide powerful tools to analyze plant gene functions through various gene manipulation technologies. Integration of different omics platforms along with gene annotation and computational analysis may elucidate a complete view in a system biology level. Extensive investigations on reverse genetics methodologies were deployed for assigning biological function to a specific gene or gene product. We provide here an updated overview of these high throughout strategies highlighting recent advances in the knowledge of functional genomics in plants.