The Caplules of Staphylococcus aureus Clinical Isolates Work as the Colonization Factor

临床分离的金黄色葡萄球菌包封率很高。然而，金黄色葡萄球菌的荚膜多糖是否与其他细菌荚膜一样具有真正的致病作用尚不清楚。报告了11种血清型，临床分离的大多数血清型为5或8型。我们观察到临床分离的人血菌具有薄层荚膜，荚膜多糖不能覆盖细胞壁。此外，高分子量的疏水蛋白（200KD和l60KD）强烈结合在胶囊表面，改变了表面的疏水特性。我们分离纯化了其中一种疏水蛋白200KD蛋白，命名为CP-PA。针对CP-PA的特异性抗体在Reynolds和Becker菌株、5型和8型标准血清型菌株上均有反应，在许多临床分离株上也有反应。从人血中分离到的疏水包封菌株NM对PMN细胞和Vero细胞具有高度的粘附性。上述结果提示金黄色葡萄球菌临床分离株荚膜多糖作为定殖因子对宿主细胞具有致病作用。

The rate of encapsulated strains of Stapylococcus aureus is very high among clinical isolates. However, it is still unclear that the capsular polysaccharide of S.aureus has the real pathogenic role as same as other bacterial capsules. Eleven serotypes of capsule are reported and most of clinical isolates belong to the serotype 5 or 8.We observed that the clinical isolates from human blood has the thin layered capsule and the capsular polysaccharide cannnot cover the cell wall teichoic acid. Furthermore, hydrophobic proteins of high molecular weight (200KD and l60KD) strongly bound to the surface of capsule and changed the surface characterisitcs to be hydrophobic. We isolated and purified 200KD protein, one of the hydrophobic proteins, and designated it as CP-PA.The specific antibody against CP-PA reacted on both strains Reynolds and Becker, standard serotype strains of type 5 and type 8 respectively, and it also reacted on many clinical isolated strains. The hydrophobic encapsulated strain NM isolated from human blood highly adhered to PMN cells and Vero cells. These results suggested that the capsular polysaccharide of S.aureus clinical isolates has the pathogenic role as colonization factor to the host cells.