变形链球菌表面蛋白P1的提取纯化

Purification of Streptococcus mutans surface protein P1

目的:探索高效率、条件温和的方法分离纯化有黏附活性的变形链球菌表面蛋白P1,为进一步分析表面蛋白P1生物学特性奠定实验基础。方法:硫酸铵分级沉淀法提取变形链球菌表面蛋白P1粗提物,在AKTA explorer100快速纯化工艺开拓系统中采用Sepharose XL填料(强阴离子交换剂)分离纯化变形链球菌表面蛋白P1。通过黏附抑制实验检测蛋白的黏附活性。结果:蛋白纯化后SDS-PAGE电泳可见分子量约185 kD的单一蛋白条带。该蛋白可明显抑制变形链球菌在唾液包被羟基磷灰石表面的黏附(P<O.05)。结论:运用硫酸铵分级盐析沉淀粗提变形链球菌表面蛋白,在AKTA explorer100快速纯化工艺开拓系统中采用强阴离子交换层析可获得较高得率的、保持黏附活性的纯化P1蛋白。

Objective： To obtain the active Streptococcus mutans P1 protein by an efficient method. Method： Extract Streptococcus mutans surface protein P1 by ammonium sulfate fractionation precipitation. The AKTA explorer100 preparative chromatography system was used to separate and purify P1 from Streptococcus mutans by strong anion exchange chromatogra- phy techniques. Result： Only one protein band of 185 kd was shown on SDS-PAGE. This protein can statistically inhibit Streptococcus mutans adherence on saliva coated hydroxyapatite. Conclusion：Streptococcus mutans surface protein P1 can be purified efficiently by the combination of ammonium sulfate fractionation precipitation and strong anion exchange chro- matography techniques applied in the AKTA explorer100 preparative chromatography system.