Polysaccharide toxin from Group B -hemolytic Streptococcus (GBS) having improved purity

摘要

The invention relates to a polysaccharide toxin from group B - hemolytic Streptococcus (GBS) having improved purity. The improved purity of the toxin, 95%, is achieved by the method of purification wherein a bacterial fermentation stock is subjected to chromatography with hydrophobic interaction chromatography (HIC) resin, extraction with a phenol/saline solution followed by ion exchange chromatography. The purified GBS toxin has a molecular weight of about 300 kD and a relative carbohydrate ratio of rhamnose:mannose:galactose:glucose:N-acetyl glucosamine:N-acetyl galactosamine of about 0:1:3:1:1:1, respectively. The GBS toxin is useful for treatment of tumors and other medical conditions.