Synthesis and antigenic analysis of the BclA glycoprotein oligosaccharide from the Bacillus anthracis exosporium
Synthesis and antigenic analysis of the BclA glycoprotein oligosaccharide from the Bacillus anthracis exosporium
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DOI：
10.1002/chem.200601245
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发表时间：
2006-12-13
影响因子：
4.3
通讯作者：
Boons, Geert-Jan
中科院分区：
文献类型：
--
作者：
Mehta, Alok S.;Saile, Elke;Boons, Geert-Jan
糖蛋白BcIA是炭疽芽孢杆菌孢子外壁的重要组成部分。该糖蛋白被寡糖取代，该寡糖由先前未知的末端糖2-O-甲基-4-（3-羟基-3-甲基丁酰氨基）-4，6-二脱氧-D-吡喃葡萄糖（也称为蒽糖）取代的β-L-鼠李糖苷组成。在B的孢子中未发现Anthrose。cereus和B.苏云金芽孢杆菌，使其成为一个潜在的物种特异性标记的B。炭疽病为了研究蒽糖的抗原性，本论文开发了一种含蒽糖的三糖及其类似物的高效合成方法。这些类似物要么在C-2位缺少甲基醚，要么含有蒽糖的修饰的C-4氨基官能团。合成的化合物配备有氨丙基间隔基以促进与载体蛋白mariculure Keyhole Limpet Hemocyanin（mcKLH）和牛血清白蛋白（BSA）的缀合。用B的活孢子或辐照孢子免疫家兔的血清抗体。炭疽菌Sterne 34 F（2）能够识别合成的三糖-mcKLH缀合物。相互作用的特异性通过与游离和BSA缀合的三聚氰胺的竞争性抑制来证实。使用三糖类似物的抑制表明，蒽糖的异戊酸部分是抗体识别的重要结构基序。这些数据表明：（1）蒽糖是B的特异性抗原决定簇。炭疽菌Sterne孢子; 2）该抗原被呈递给接受炭疽活孢子疫苗的兔的免疫系统; 3）寡糖的合成类似物保留抗原结构;和4）抗原区域定位于寡糖的特定末端基团。总的来说，这些数据为合成和开发用于检测和靶向B中非蛋白质结构的孢子特异性试剂提供了重要的概念验证步骤。炭疽病
The glycoprotein BcIA is an important constituent of the exosporium of Bacillus anthracis spores. This glycoprotein is substituted with an oligosaccharide composed of a beta-L-rhamnoside substituted with the previously unknown terminal saccharide, 2-O-methyl-4-(3-hydroxy-3-methylbutana- mido)-4,6-dideoxy-D-glucopyranose, also referred to as anthrose. Anthrose has not been found in spores of B. cereus and B. thuringiensis, making it a potential species-specific marker for B. anthracis. In order to study the antigenicity of anthrose, efficient syntheses of an anthrose-containing trisaccharide and a series of structurally related analogues were developed. The analogues lacked either the methyl ether at C-2 or contained modified C-4 amino functionalities of anthrose. The synthetic compounds were equipped with an aminopropyl spacer to facilitate conjugation to the carrier proteins maricullure Keyhole Limpet Hemocyanin (mcKLH) and bovine serum albumin (BSA). Serum antibodies of rabbits immunized with live or irradiated spores of B. anthracis Sterne 34F(2) were able to recognize the synthetic trisaccharide-mcKLH conjugate. The specificity of the interaction was confirmed by competitive inhibition with the free-and BSA-conjugated trisaccharides. Inhibition using the trisaccharide ana-logues demonstrated that the isovaleric acid moiety of anthrose is an important structural motif for antibody recognition. These data demonstrate that 1) anthrose is a specific antigenic determinant of the B. anthracis Sterne spore; 2) this antigen is presented to the immune system of rabbits receiving the anthrax live-spore vaccine; 3) synthetic analogues of the oligosaccharide retain the antigenic structure; and 4) the antigenic region is localized to specific terminal groups of the oligosaccharide. Collectively these data provide an important proof-of-concept step in the synthesis and development of spore-specific reagents for detection and targeting of non-protein structures in B. anthracis.