抄録
The endotoxin or O-antigen of Shigella flexneri 2b (K3) has been separated into three components of which only one is biologically active by zone electrophoresis according to Kunkel's method using M/20 borate buffer pH 9.0. The active substance which moves fastest toward the cathode was further separated with calcium phosphate gel into two fractions, lipid-peptide-polysaccharide and polyuronide. The endotoxin thus prepared contained 18% lipid, 24% peptide and 52% polysaccharide. Amino acids detected in the peptide fraction of purified endotoxin were lysine, tyrosine, alanine, and cystine. Polysaccharide was composed of rhamnose, glucose, N-acetylglucosamine (approximately 4:2:1) and uronic acid. By Ouchterlony's agar-diffusion method, the purified endotoxin was shown to be immunologically homogeneous.
