Glycoprotein for the protection of liposomes

New glycoprotein comprised of 14 % of carbohydrate and 86 % of protein; the glycidic part has a molar ratio of glucose : galactose : N-acetylglucosamine : N-acetylgalastosamine of 1.00 : 0.14 : 0.18 : 0.33; and the proteinic part has the following aminoacid composition: aspartic acid, 7.87; threonine, 10.6; serine, 8.03; glutamic acid, 7.99; proline, 4.12; glycine, 8.42, alanine, 11.04; valine, 5.36; methionine, 1.86; isoleucine, 2.91; leucine, 4.80; tyrosine, 1.58; phenylalaine, 2.61; histidine, 13.86; lysine, 4.87 and arginine, 4.0. It is obtained by culture of the new bacterial species Pseudoalteromonas antarctica CECT4664. It is useful for the coating of liposomes in order to improve their stability in relation to external factors such as surfactants, with the additional advantage to act also as cryoprotector.