GLUCOSYLTRANSFERASE MEDIATES ADHESION OF STREPTOCOCCUS-GORDONII TO HUMAN ENDOTHELIAL-CELLS IN-VITRO
GLUCOSYLTRANSFERASE MEDIATES ADHESION OF STREPTOCOCCUS-GORDONII TO HUMAN ENDOTHELIAL-CELLS IN-VITRO
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DOI：
10.1128/iai.62.6.2187-2194.1994
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发表时间：
1994-06-01
影响因子：
3.1
通讯作者：
STINSON, MW
中科院分区：
文献类型：
--
作者：
VACCASMITH, AM;JONES, CA;STINSON, MW
以人脐静脉内皮细胞为实验宿主模型，探讨感染性心内膜炎链球菌黏附的机制(S)。戈登链球菌的黏附活性在对数生长期达到最大，用热、甲醛或胰酶处理细菌后，黏附活性大大降低或消除。在链球菌数量饱和时，每个HUVEC平均结合81个细菌。低分子右旋糖苷和肝素可抑制链球菌的黏附，而蔗糖、纤维连接蛋白或层粘连蛋白则不能。用10 mM EDTA从戈登葡萄球菌表面解离的蛋白或从废培养基中分离的蛋白对HUVEC的黏附也有预防作用。Western印迹(免疫印迹)检测到HUVEC与链球菌粗提物孵育后，有一种153 kDa的粘附素蛋白(AP153)。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法表明，粘附素与蔗糖和Triton X-100孵育后具有葡萄糖转移酶(GTF)活性。经葡聚糖珠亲和层析纯化的AP153具有与人脐静脉内皮细胞的结合活性、GTF活性、与戈登链球菌GTF相似的氨基酸组成和抑制戈登链球菌黏附的能力。链球菌与粘附素抗体孵育可抑制细菌与HUVEC单层的附着。这些结果表明，表面定位的GTF在体外介导了戈登葡萄球菌与HUVEC的黏附，可能是感染性心内膜炎时心内膜定植的机制之一。
Human umbilical vein endothelial cells (HUVEC) were used as an experimental host model to investigate the mechanism(s) of streptococcal adhesion in infective endocarditis. Adhesion activity of Streptococcus gordonii was maximal during the logarithmic phase of growth and was greatly reduced or eliminated by pretreatment of bacteria with heat, formaldehyde, or trypsin. At saturating numbers of streptococci, an average of 81 bacteria were bound per HUVEC. Streptococcal adhesion was inhibited by low-molecular-weight dextran and heparin but not by sucrose, fibronectin, or laminin. Adhesion was also prevented by pretreatment of HUVEC with proteins dissociated from the surface of S. gordonii with 10 mM EDTA or isolated from spent culture medium. Western blot (immunoblot) assays detected a single adhesin protein of 153 kDa (AP153) on HUVEC after incubation with unfractionated extracts of streptococci. The adhesin exhibited glucosyltransferase (GTF) activity when incubated with sucrose and Triton X-100 after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The AP153 was purified by affinity chromatography on dextran beads and shown to have binding activity for HUVEC, GTF activity, an amino acid composition similar to that reported for GTF of S. gordonii, and the ability to inhibit S. gordonii adhesion. Incubation of the streptococci with antibodies to the adhesin inhibited bacterial attachment to HUVEC monolayers. These results indicate that surface-localized GTF mediates adhesion of S. gordonii to HUVEC in vitro and may serve as a mechanism for colonization of the endocardium in infective endocarditis.