The bundlin pilin protein of enteropathogenic Escherichia coli is an N-acetyllactosamine-specific lectin
The bundlin pilin protein of enteropathogenic Escherichia coli is an N-acetyllactosamine-specific lectin
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DOI：
10.1111/j.1462-5822.2007.01028.x
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发表时间：
2008-01-01
影响因子：
3.4
通讯作者：
Armstrong, Glen D.
中科院分区：
文献类型：
--
作者：
Hyland, Romney M.;Sun, Jiangxiao;Armstrong, Glen D.
合成N-乙酰乳糖胺(LacNAc)糖苷序列偶联牛血清白蛋白(BSA)竞争性地抑制肠病原性大肠杆菌(EPEC)对人肠道活检标本和组织培养细胞单层的定位黏附(LA)。LacNAc特异的粘附素似乎与EPEC在定植早期阶段表达的束形成丸(BFP)有关。在此，我们报道了重组bundlin抑制EPEC LA对Hep-2细胞的作用，并与Hep-2细胞结合。重组Bundlin还与合成的LacNAc-苯和LacNAc-O(CH2)(8)CONH2糖苷结合，用毫摩尔结合常数(K-Assoc)，用纳米电喷雾电离质谱仪进行鉴定。此外，LacNAc-BSA只抑制表达a bundlin等位基因的EPEC菌株的LA，这表明LacNAc结合口袋可能位于a bundlin单体中。综上所述，这些结果表明，αbundlin具有凝集素样属性，这是LacNAc特异性表达αbundlin的EPEC菌株最初与宿主肠上皮细胞黏附的原因。
Synthetic N-acetyllactosamine (LacNAc) glycoside sequences coupled to BSA competitively inhibit enteropathogenic Escherichia coli (EPEC) localized adherence (LA) to human intestinal biopsy specimens and tissue culture cell monolayers. The LacNAc-specific adhesin appears to be associated with the bundle-forming pill (BFP) expressed by EPEC during the early stages of colonization. Herein, we report that recombinant bundlin inhibits EPEC LA to HEp-2 cells and binds to HEp-2 cells. Recombinant bundlin also binds, with millimolar association constants (K-assoc) to synthetic LacNAc-Benzene and LacNAc-O(CH2)(8)CONH2 glycosides as assessed in the gas phase by nanoelectrospray ionization mass spectrometry. Furthermore, LacNAc-BSA inhibits LA only of EPEC strains that express a bundlin alleles, suggesting putative locations for the LacNAc-binding pocket in the a bundlin monomer. Collectively, these results suggest that alpha bundlin possesses lectin-like properties that are responsible for LacNAc-specific initial adherence of alpha bundlin-expressing EPEC strains to host intestinal epithelial cells.