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.