变形链球菌脂磷壁酸的提纯及鉴定

Purification and characterization of lipoteichoic acid from Streptococcus Sobronus

采用酚水提取,Sepharose 6B凝胶过滤,氯仿和甲醇处理,DEAE—Sephace离子交换层析纯化,从变形链球菌S.sobrinus 6715中提纯出细菌胞壁结构脂磷壁酸。经红外光谱和核磁共振波谱分析,以sigama标准品为参照,证实是磷酸甘油结构,并含有生物活性的丙氨酸和糖取代基。

Lipoteichoic acid (LTA) is amphipathic molecule found in cell surface of gram-positive bacteria. Although there were some hy-pothese about adhesion of LTA, the role of LTA in bacterial pathogenicety is still unclear. For this reason,a serial studies of LTA were carried out. In this study LTA was ex- traded by hot aqueous phenol from Streptococcus Sobronus 6715 grown in tryptic soy both supplemented with 5% sucrose for 17 hours, and was purified on gel filtration by Sepharose 6B, chloroform-methanol precipitation and chromatography on DEAE-Sepha-cel. The purified LTA was characterized by FT-IR and 1H- NMR with standard sample of LTA (Sigma Co) as control. The results showed that LTA contains alanine ester and glycosyl residues which take important role in the amphipathic molecule.