Characterization of sugar recognition by the toxin complex produced by Clostridium botulinum serotype C variant strain Yoichi
Characterization of sugar recognition by the toxin complex produced by Clostridium botulinum serotype C variant strain Yoichi
复制标题
肉毒杆菌血清型 C 变体菌株 Yoichi 产生的毒素复合物的糖识别特性
DOI：
10.1111/j.1574-695x.2011.00825.x
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
T.
中科院分区：
文献类型：
--
作者：
Matsuo;T.;Miyata;K.;Inui;K.;Ito;H.;Horiuchi;R.;Suzuki;T.;Yoneyama;T.;Oguma;K.;Niwa;K.;Watanabe;T.;Ohyama;T.
C型肉毒杆菌产生一种神经毒素（BoNT）和无毒蛋白，包括无毒的非血凝素和三种血凝素亚组分HA-70、HA-33和HA-17，形成一个大的毒素复合物（L-TC）。血清C型菌株产生的L-TC通常通过HA-33与红细胞上的唾液酸结合而表现出血凝（HA）活性，而血清C型菌株Yoichi (C-Yoichi) L-TC既不表现出HA活性，也不表现出与红细胞的结合活性，可能是由于HA-33蛋白的C端截断。然而，在这里，我们证明C-Yoichi L-TC对神经氨酸酶处理的红细胞显示出充分的HA和结合活性，这种活性在半乳糖（Gal）或乳糖（Lac）存在下完全被抑制。与未处理的IEC-6细胞相比，经神经氨酸酶处理的C-Yoichi L-TC与大鼠小肠上皮细胞的结合也显著增强。同样，从C-Yoichi L-TC中分离的HA-33/HA-17复合物也能与神经氨酸酶处理的IEC-6细胞结合。在Gal或Lac的存在下，L-TC和HA-33/HA-17的结合活性均受到抑制。此外，C-Yoichi L-TC与乳糖亲和凝胶柱紧密吸附。这些结果强烈表明，细胞上Gal片段的不寻常识别可能是由于独特的C-Yoichi HA-33蛋白的c端一半的变异和/或截断。
Clostridium botulinumserotype C strains produce a neurotoxin (BoNT) along with nontoxic proteins, including nontoxic nonhemagglutinin and three hemagglutinin subcomponents, HA-70, HA-33 and HA-17, to form a large toxin complex (L-TC). While L-TCs produced by serotype C strains usually exhibit hemagglutination (HA) activity via HA-33 binding to sialic acid on erythrocytes, serotype C strain Yoichi (C-Yoichi) L-TC exhibited neither HA nor binding activity towards erythrocytes, probably due to a C-terminal truncation of the HA-33 protein. However, here, we demonstrate that C-Yoichi L-TC newly showed full HA and binding activity towards neuraminidase-treated erythrocytes that was completely inhibited in the presence of galactose (Gal) or lactose (Lac). Binding of C-Yoichi L-TC to rat small intestine epithelial cells (IEC-6) treated with neuraminidase was also significantly enhanced compared with untreated IEC-6 cells. Similarly, the HA-33/HA-17 complex isolated from C-Yoichi L-TC also bound to neuraminidase-treated IEC-6 cells. The binding activity of both L-TC and HA-33/HA-17 was inhibited in the presence of Gal or Lac. Additionally, C-Yoichi L-TC adsorbed tightly to a lactose-affinity gel column. These results strongly suggest that the unusual recognition of the Gal moiety on the cells could be due to a variation and/or a truncation in the C-terminal-half of the unique C-Yoichi HA-33 protein.