Pertussis toxin has eukaryotic-like carbohydrate recognition domains.
Pertussis toxin has eukaryotic-like carbohydrate recognition domains.
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DOI：
10.1073/pnas.89.1.118
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发表时间：
1992
影响因子：
11.1
通讯作者：
K. Saukkonen;W. Burnette;V. Mar;H. Masure;E. Tuomanen
中科院分区：
文献类型：
--
作者：
K. Saukkonen;W. Burnette;V. Mar;H. Masure;E. Tuomanen
百日咳杆菌通过包括百日咳毒素在内的多种粘附素与人纤毛和巨噬细胞上的糖偶联物结合。对百日咳毒素B寡聚体的细胞识别特性进行了表征，并通过重组百日咳毒素亚单位的定点突变，确定了识别区域的位置和结构要求。纤毛和巨噬细胞的识别分别定位于B寡聚体的S2和S3亚基。尽管这些亚基之间的序列同源性超过80%，但纤毛状乳糖基神经酰胺只能识别S2，而白细胞神经节苷脂只能结合S3。S2中第44、45、50或51位残基的替换导致碳水化合物识别从乳糖基神经酰胺转移到神经节苷脂。S2和S3之间37-52个氨基酸残基的突变交换改变了它们的碳水化合物和靶细胞特异性。将这些碳水化合物识别序列与植物和动物凝集素的序列进行比较，发现原核凝集素功能所必需的区域与真核细胞中C型碳水化合物识别结构域的一个子集密切相关。
Bordetella pertussis is bound to glycoconjugates on human cilia and macrophages by multiple adhesins, including pertussis toxin. The cellular recognition properties of the B oligomer of pertussis toxin were characterized and the location and structural requirements of the recognition domains were identified by site-directed mutagenesis of recombinant pertussis toxin subunits. Differential recognition of cilia and macrophages, respectively, was localized to subunits S2 and S3 of the B oligomer. Despite greater than 80% sequence homology between these subunits, ciliary lactosylceramide exclusively recognized S2 and leukocytic gangliosides bound only S3. Substitution at residue 44, 45, 50, or 51 in S2 resulted in a shift of carbohydrate recognition from lactosylceramide to gangliosides. Mutational exchange of amino acid residues 37-52 between S2 and S3 interchanged their carbohydrate and target cell specificity. Comparison of these carbohydrate recognition sequences to those of plant and animal lectins revealed that regions essential for function of the prokaryotic lectins were strongly related to a subset of eukaryotic carbohydrate recognition domains of the C type.