Placenta-specific tissue protein PP.sub.10

An isolated, concentrated tissue protein, PP.sub.10, obtained by fractionating a placental extract or an aqueous solution obtained from such an extract, said tissue protein having:

• (a) a protein proportion of 93.+-.3%;
• (b) an amino acid analysis of
• ______________________________________ Variation mol % Coefficient (%) ______________________________________ lysine 6.51 1.55 histidine 1.81 5.21 arginine 3.67 2.24 aspartic acid 9.82 0.79 threonine 5.20 3.32 serine 7.32 3.91 glutamic acid 11.50 0.54 proline 5.16 2.76 glycine 6.97 1.71 alanine 7.74 4.70 cystine/2 1.94 3.45 valine 6.32 6.54 methionine 2.43 4.54 isoleucine 4.09 1.97 leucine 9.46 2.63 tyrosine 2.96 8.88 phenylalanine 5.44 1.13 tryptophan 1.69 7.04 ______________________________________
• (c) a carbohydrate proportion of 6.65.+-.1.55%, consisting of 4.8.+-.1.0% of hexoses, 1.2.+-.0.3% of hexosamine, 0.05.+-.0.05% of fucose, and 0.6.+-.0.2% of sialic acid;
• (d) a sedimentation coefficient S.sub.20/w.sup.o, of 3.8.+-.0.2 S;
• (e) a molecular weight determined in the ultracentrifuge of 48,000.+-.5,000;
• (f) a molecular weight determined in sodium dodecylsulfate-containing polyacrylamide gel of 65,000.+-.5,000;
• (g) an extinction coefficient E.sub.1 cm.sup.1% (280 nm) of 10.9.+-.0.5;
• (h) an electrophoretic mobility in the range of the .alpha..sub. 1-globulins;
• and
• (i) an isoelectric point of 5.1.+-.0.3.