Peumans W J, Van Damme E J, Barre A, Rougé P
Laboratory for Phytopathology and Plant Protection, Katholieke Universiteit Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium.
Adv Exp Med Biol. 2001;491:27-54. doi: 10.1007/978-1-4615-1267-7_3.
The majority of plant lectins can be classified in seven families of structurally and evolutionary related proteins. Within a given lectin family most but not necessarily all members are built up of protomers with a similar primary structure and overall 3-D fold. The overall structure of the native lectins is not only determined by the structure of the protomers but depends also on the degree of oligomerization and in some cases on the post-translational processing of the lectin precursors. In general, lectin families are fairly homogeneous for what concerns the overall specificity of the individual lectins, which illustrates that the 3-D structure of the binding site has been conserved during evolution. In the case of the jacalin-related lectins the occurrence of a mannose- and galactose-binding subfamily can be explained by the fact that a post-translational cleavage of the protomers (of the galactose-binding subfamily) yields a slightly altered binding site. Unlike the other families, the legume lectins display a wide range of specificites, which is clearly reflected in the occurrence of sugar-binding sites with a different 3-D structure.
大多数植物凝集素可分为七个结构和进化相关蛋白家族。在给定的凝集素家族中，大多数（但不一定是所有）成员由具有相似一级结构和整体三维折叠的原聚体组成。天然凝集素的整体结构不仅由原聚体的结构决定，还取决于寡聚化程度，在某些情况下还取决于凝集素前体的翻译后加工。一般来说，就单个凝集素的整体特异性而言，凝集素家族相当同质，这说明结合位点的三维结构在进化过程中得到了保留。在与jacalin相关的凝集素中，甘露糖和半乳糖结合亚家族的出现可以解释为（半乳糖结合亚家族的）原聚体的翻译后切割产生了略有改变的结合位点。与其他家族不同，豆科凝集素表现出广泛的特异性，这在具有不同三维结构的糖结合位点的出现中得到了明显体现。
