Chemical characterization of Rauscher leukaemia virus proteins

The proteins of Rauscher murine leukaemia virus (R-MuLV) were characterized by amino acid analyses and by determination of their mol. wt. by gel filtration on cross-linked Sepharose 6B in 6M-guanidine hydrochloride (GuHCl). Molecular weights of 56,000, 29,000, 15,000, 10,500 and 7,600 were found for gp70, p30, p15, p12 and p10 respectively. The amino acid compositions of these proteins and of p12E have been determined. The amino acid compositions of the p10 polypeptides of Rauscher-MuLV and Moloney-MuLV are very similar as are those of the p30 polypeptides, whereas the amino acid compositions of the p12 polypeptides differ considerably. P12E contains the highest percentage of hydrophobic amino acid residues. Among the gag-gene coded proteins, p15 contains the highest percentage of hydrophobic amino acid residues while p12 and p10 contain the lowest.