Production of Immunoabsorbent Nanoparticles by Displaying Single-Domain Protein A on Potato Virus X.

The combination of antibodies with nanoparticles provides wide-ranging applications in biosensing. While several covalent presentation strategies have been established, there is need for alternative, non-covalent methods to provide a routine for scalable nanomanufacturing. We report the multivalent presentation of the B domain of Staphylococcus aureus protein A (SpAB) on potato virus X (PVX) nanoparticles.

Genetic engineering and chemical conjugation of potato virus X.

Here we report the genetic engineering and chemical modification of potato virus X (PVX) for the presentation of various peptides, proteins, and fluorescent dyes, or other chemical modifiers. Three different ways of genetic engineering are described and by these means, peptides are successfully expressed not only when the foot and mouth disease virus (FMDV) 2A sequence or a flexible glycine-serine linker is included, but also when the peptide is fused directly to the PVX coat protein. When larger proteins or unfavorable peptide sequences are presented, a partial fusion via the FMDV 2A sequence is preferable.

Immunogenic properties of chimeric potato virus X particles displaying the hepatitis C virus hypervariable region I peptide R9.

The immunogenic properties of chimeric potato virus X (PVX) particles engineered to display the synthetic R9 peptide have been evaluated. The R9 peptide is a consensus sequence derived from diverse variants of the hypervariable region 1 from the hepatitis C virus (HCV) envelope protein E2. Two different constructs were designed, with the R9 peptide expressed either as an indirect fusion via the ribosomal skip 2A (PVX(R9-2A)CP) sequence or as a direct PVX coat protein fusion (PVX(R9)CP).

Characterization and diagnostic potential of foreign epitope-presenting Ty1 virus-like particles expressed in Escherichia coli and Pichia pastoris.

We expressed a truncated p1 protein (p1-379) from the Saccharomyces cerevisiae retrotransposon Ty1 in the cytosol of Escherichia coli and Pichia pastoris, achieving maximum expression levels of 20 and 65 mg/l, respectively. Two well-characterized epitopes from beet necrotic yellow vein virus (BNYVV) were used to evaluate the virus-like particles (VLPs) as a presentation system for synthetic antigens. The epitopes were placed near the externally located N-terminus and at the internally located C-terminus of the p1 protein.

Grapevine fanleaf virus (GFLV)-specific antibodies confer GFLV and Arabis mosaic virus (ArMV) resistance in Nicotiana benthamiana.

Grapevine fanleaf virus (GFLV) is one of the most destructive pathogens of grapevine. In this study, we generated monoclonal antibodies binding specifically to the coat protein of GFLV. Antibody FL(3), which bound most strongly to GFLV and showed cross-reactivity to Arabis mosaic virus (ArMV), was used to construct the single-chain antibody fragment scFvGFLVcp-55.

Generation and characterization of a recombinant antibody fragment that binds to the coat protein of grapevine leafroll-associated virus 3.

Pathogen-specific recombinant antibodies have been used to characterize pathogen infections and to engineer resistance in crops. We selected a single-chain antibody fragment (scFvLR3cp-1) specific for the coat protein of grapevine leafroll-associated virus 3 (GLRaV-3), one of the agents of grapevine leafroll (GLR) disease, from a phage display library. The antibody binds specifically to the entire length of GLRaV-3 particles and has a high binding affinity value (K(D)) of 42 nM.