Functional heterogeneity of type 1 fimbriae of Escherichia coli.
Functional heterogeneity of type 1 fimbriae of Escherichia coli.
复制标题
大肠杆菌 1 型菌毛的功能异质性。
DOI：
10.1128/iai.60.11.4709-4719.1992
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发表时间：
1992
影响因子：
3.1
通讯作者：
Hasty,DL
中科院分区：
文献类型：
--
作者：
Sokurenko,EV;Courtney,HS;Abraham,SN;Klemm,P;Hasty,DL
大肠杆菌和肠杆菌科的其他成员表达促进细菌粘附到宿主受体的表面纤维状结构，即菌毛。1型菌毛具有凝集素样成分FimH，其通常被认为引起与宿主受体的含甘露糖寡糖结合。由于1型菌毛微生物的粘附被甘露糖抑制，因此该反应被描述为甘露糖敏感性（MS）。我们研究了大肠杆菌CSH-50株1型菌毛的粘附性。大肠杆菌（其仅表达1型菌毛）与纤连蛋白（FN）。E. coliCSH-50不能结合可检测量的可溶性FN，但能很好地粘附于固定的血浆或细胞FN。这种粘附被含甘露糖的甘露醇抑制。利用纯化的FN结构域，发现E. coli CSH-50主要以MS方式粘附于氨基末端和明胶结合结构域，其中只有一个是糖基化的。甘露糖特异性凝集素伴刀豆球蛋白A结合FN和卵清蛋白被消除或减少，分别与高碘酸盐或糖苷内切酶孵育。E. coli CSH-50对卵清蛋白的粘附性降低，但对FN的粘附性不受影响。E. coli CSH-50也以MS方式粘附于复制氨基末端FN结构域（FNsp 1）的一部分的合成肽。纯化的CSH-50菌毛结合固定FN和FNsp 1在MS的方式和抑制完整的生物体的粘附。然而，从HB 101（pPKL 4）中纯化的菌毛既不与FN或FNsp 1结合，也不抑制E. coli粘附于固定的FN或FNsp 1。这些新的发现表明，有两种形式的1型MS菌毛。一种形式仅表现出公知的MS凝集素样活性，其需要含甘露糖的糖蛋白的基质。另一种形式不仅表现出MS凝集素样活性，而且以MS方式结合蛋白质的非糖基化区域。
Escherichia coli and other members of the family Enterobacteriaceae express surface fibrillar structures, fimbriae, that promote bacterial adhesion to host receptors. Type 1 fimbriae possess a lectinlike component, FimH, that is commonly thought to cause binding to mannose-containing oligosaccharides of host receptors. Since adhesion of type 1 fimbriated organisms are inhibited by mannose, the reactions are described as mannose sensitive (MS). We have studied the adhesion of the type 1 fimbriated CSH-50 strain of E. coli (which expresses only type 1 fimbriae) to fibronectin (FN). E. coli CSH-50 does not bind detectable amounts of soluble FN but adheres well to immobilized plasma or cellular FN. This adhesion was inhibited by mannose-containing saccharides. By using purified domains of FN, it was found that E. coli CSH-50 adheres primarily to the amino-terminal and gelatin-binding domains, only one of which is glycosylated, in an MS fashion. Binding of the mannose-specific lectin concanavalin A to FN and ovalbumin was eliminated or reduced, respectively, by incubation with periodate or endoglycosidase. Adhesion of E. coli CSH-50 to ovalbumin was reduced by these treatments, but adhesion to FN was unaffected. E. coli CSH-50 also adheres to a synthetic peptide copying a portion of the amino-terminal FN domain (FNsp1) in an MS fashion. Purified CSH-50 fimbriae bound to immobilized FN and FNsp1 in an MS fashion and inhibited adhesion of intact organisms. However, fimbriae purified from HB101 (pPKL4), a recombinant strain harboring the entire type 1 fim gene locus and expressing functional type 1 fimbriae, neither bound to FN or FNsp1 nor inhibited E. coli adhesion to immobilized FN or FNsp1. These novel findings suggest that there are two forms of type 1 MS fimbriae. One form exhibits only the well-known MS lectinlike activity that requires a substratum of mannose-containing glycoproteins. The other form exhibits not only the MS lectinlike activity but also binds to nonglycosylated regions of proteins in an MS manner.