"

From 2012.igem.org

Introduction

The Wageningen UR team 2012 has worked on the modification of virus-like particles (VLPs) to make them interesting platforms for vaccine production and/or site specific drug delivery. VLPs are empty virus capsids, meaning that they do not contain any viral genome and proteins except for the coat proteins. Coat proteins of some viruses have shown the ability to self-assemble in absence of its viral genome and other viral proteins, and thus form VLPs.

Besides the work done in the wet lab on VLPs, the team developed a web based tool that simplifies the design of the best cloning strategy: The Constructor. The team cooperated with the 2011 Wageningen UR iGEM team. Their experiences were used to further develop the tool adding features and making a user-friendly and easily accessible tool. This work has already been published.

The Virus-Like Particle project

To facilitate the attachment of ligands and epitopes, we want to put anchors on the outside of the VLPs, and anchors on the inside to attach medicine, which is then encapsulated by the VLP. The anchors that we want to use are charged coils, which are already being used to encapsulate GFP into Cowpea Chlorotic Mottle Virus (CCMV) VLPs. This technique relies on charged coil peptides (negatively charged E-coil and positively charged K-coil) that can form ion bonds together. We want to use this technique to obtain a universal attachment system with which we can attach all kinds of epitopes to the VLPs. We selected 3 viruses that we want to use to produce VLPs with auniversal attachment system on the inside and outside of the VLPs. We have selected them based on existing experience at Wageningen University, increasing the probability of success and their promising structure. Besides CCMV, we will use the Hepatitis B core antigen VLP for the production of vaccines. The Potato Leaf Roll virus (PLRV) will be used to yield a newly expressed VLP in E. coli, because of its promising structure with outside spikes that are easy to modify. All three VLPs will be expressed in E. coli and all three will need to be submitted in the same standardized form for the competition. Formation of VLPs is usually confirmed using Electron Microscopy (EM). This is rather time consuming and expensive, so Dynamic Light Scattering (DLS) is investigated as an alternative method. DLS can provide an indication of VLP formation but conclusive evidence should be obtained by EM. VLPs can have many applications in the health industry, but they can also find their way in the development of bio-nano materials and processing engineering.