The primary structure of papaya mosaic virus coat protein

The amino acid sequence of the coat protein of the potexvirus papaya mosaic virus (PMV) has been determined, using a combination of the Edman degradation procedure (manual and automated) and mass spectrometry. The amino acid sequence is compared with that of the coat protein of potato virus X (PVX) as reported (S. Yu. Morozov, V. M. Zakhariev, B. K. Chernov, V. S. Prasolov, Yu. V. Kozlov, J. G. Atabekov, and K. G. Skyabin, Dokl. Acad. Nauk, SSSR 271, 211-215,1983). PMV has 73 of 211 amino acid residues in common with PVX and has 25 fewer residues in the polypeptide chain. Also 10 of a possible 16 proline residues are in similar positions in both proteins, including a sequence of 3 prolines at the carboxyl end. Furthermore, the 2 cysteine residues in PMV correspond with 2 of the 3 cysteines in PVX