Nucleotide sequence of the putative replicase gene of the sour cherry strain of plum pox potyvirus

The complete nucleotide sequence of the NIb coding region of the sour cherry strain of plum pox potyvirus (PPV-SoC) has been determined. It consists of 1554 nucleotides and encodes a putative replicase protein of 518 amino acids. Sequence identity scores between NIb of PPV-SoC and other isolates of PPV are significantly low (c. 78%). Many of the nucleotide substitutions, however, are silent. PPV-SoC differs from isolates of PPV-D, PPV-M and PPV-El Amar at multiple amino acid positions that are conserved between the other isolates. The NIb sequence extends the PPV-SoC sequence presently available to 2781 nt from the 3' end (similar to 28% of the genome).