Crystal structure of a shark single-domain antibody V region in complex with lysozyme
Crystal structure of a shark single-domain antibody V region in complex with lysozyme
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DOI：
10.1126/science.1101148
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发表时间：
2004-09-17
期刊：
影响因子：
56.9
通讯作者：
Wilson, IA
中科院分区：
文献类型：
--
作者：
Stanfield, RL;Dooley, H;Wilson, IA
软骨鱼是已知具有脊椎动物适应性免疫系统组分的遗传学上最古老的活生物体。其免疫应答的关键是称为新抗原受体（IgNAR）的重链同型二聚体免疫球蛋白，其中可变（V）结构域识别仅具有单个免疫球蛋白结构域的抗原，类似于骆驼科动物重链V结构域。与鸡蛋清溶菌酶（HEL）复合的I型IgNAR V结构域的1.45埃分辨率晶体结构揭示了最小的抗原结合结构域，其仅含有三个常规互补决定区中的两个，但仍然通过大小与常规抗体相当的结合界面以纳摩尔亲和力结合HEL。
Cartilaginous fish are the phylogenetically oldest living organisms known to possess components of the vertebrate adaptive immune system. Key to their immune response are heavy-chain, homodimeric immunoglobulins called new antigen receptors (IgNARs), in which the variable (V) domains recognize antigens with only a single immunoglobulin domain, akin to camelid heavy-chain V domains. The 1.45 angstrom resolution crystal structure of the type I IgNAR V domain in complex with hen egg-white lysozyme (HEL) reveals a minimal antigen-binding domain that contains only two of the three conventional complementarity-determining regions but still binds HEL with nanomolar affinity by means of a binding interface comparable in size to conventional antibodies.