A polynucleotide that encodes at least one engineered FMDV P1 precursor polypeptide that comprises at least one Tobacco Etch virus (TEV) protease cleavage site in at least one junction between VP4 and VP2, VP2 and VP3, VP3 and VP1, or VP1 and 2A components of the engineered FMDV P1 precursor polypeptide,
- the polynucleotide further encoding an engineered FMDV 3C protease that is at least 95% identical to a FMDV 3C protease described by SEQ ID NO:
- 2, 4, 6, 8, 10, 12, 14, 16, 18 20, 86, 88, 90 or 92, wherein the encoded engineered FMDV 3C protease contains a C163A substitution, and further encoding at least one potyvirus TEV protease.