Preparation of truncated orf virus entry fusion complex proteins by chemical synthesis

Members of the Chordopoxvirinae subfamily possess an unusual 11 protein entry–fusion complex (EFC) that is highly conserved and present in all species. The mode of action of this EFC is unknown, and the interactions of the constituent proteins are uncharacterised. Here, we present the chemical synthesis of membrane domain truncated linear constructs of two EFC proteins in orf virus, ORFV036 and 049. By using Boc solid phase peptide synthesis and native chemical ligation methods, these truncated proteins have been readily prepared in milligram quantities. These robust synthetic protocols allow ready access to these polypeptides to facilitate biological studies. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd. Orf virus requires an unusually large ≥11‐protein entry fusion complex to enter host cells. Through chemical synthesis, we have prepared truncated constructs of two of these entry fusion proteins (ORFV036 and 049), which were previously found to be intractable to bacterial expression. The robust synthetic protocols used allow access to milligram quantities in high purity for further biological studies.