The structure of the lentil (Lens culinaris) lectin. Amino acid sequence determination and prediction of the secondary structure.
The structure of the lentil (Lens culinaris) lectin. Amino acid sequence determination and prediction of the secondary structure.
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小扁豆（Lens culinaris）凝集素的结构。
DOI：
10.1016/s0021-9258(19)69237-9
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
A. Strosberg
中科院分区：
文献类型：
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作者：
A. Foriers;E. Lebrun;R. van Rapenbusch;R. D. De Nève;A. Strosberg
测定了从扁豆 (LcL) 种子中提取的凝集素的亚基结构和完整氨基酸序列。在之前的研究中，α链 (Mr = 5,710) 的一级结构被证明与豌豆凝集素、蚕豆葡萄糖特异性凝集素以及刀豆球蛋白 A 序列中间区域（残基 70-121）的α链同源。 β 链 (Mr = 17,572) 的完整氨基酸序列由 11 种胰蛋白酶肽、4 种通过化学裂解 β 链的三个色氨酸残基衍生的肽、用金黄色葡萄球菌蛋白酶消化后获得的 11 种肽和来自琥珀酰化多肽链的 5 种胰蛋白酶肽确定。通过将 L. culinaris 凝集素的 α 链和 β 链与位于 1 至 45 和 70 至 237 之间的刀豆球蛋白 A 部分进行比对，存在广泛的同源性，这表明 L. culinaris 和刀豆凝集素是从彼此进化而来的。对 C. ensiformis 凝集素的二级结构和通过两种不同方法预测的 L. culinaris 凝集素的可能二级结构进行了比较。结果表明，这两种多肽的折叠在进化过程中得到了特别好的保守。据建议，L. culinaris 凝集素被合成为单个多肽链，随后被切割成两个或可能的三个片段，其中两个片段是α和β，第三个是与刀豆球蛋白A中的46至69部分同源的片段。与favin一样，假定参与疏水空腔形成的氨基酸以及糖和金属结合位点在L. culinaris 凝集素中高度保守。
The subunit structure and complete amino acid sequence of the lectin extracted from Lens culinaris (LcL) seeds was determined. In previous studies, the primary structure of the alpha-chain (Mr = 5,710) was shown to be homologous to the alpha-chain of the lectin from Pisum sativum, the Vicia cracca glucose-specific lectin, and a region in the middle of the concanavalin A sequence (residues 70-121). The complete amino acid sequence of the beta-chain (Mr = 17,572) has been determined from 11 tryptic peptides, 4 peptides derived by chemical cleavage of the beta-chain at its three tryptophan residues, 11 peptides obtained after digestion with Staphylococcus aureus protease, and 5 tryptic peptides from the succinylated polypeptide chain. The extensive homologies by alignment of the alpha- and beta-chains of the L. culinaris lectin with portions of concanavalin A situated between 1 to 45 and 70 to 237, suggest that the L. culinaris and Canavalia ensiformis lectins have evolved from each other. A comparison was made between the secondary structure of the C. ensiformis lectin and the probable secondary structure of the L. culinaris lectin as predicted by two different methods. The results indicate that the folding of these two polypeptides has been particularly well conserved during evolution. It is suggested that the L. culinaris lectin is synthesized as a single polypeptide chain and cleaved subsequently into two or possibly three fragments, two of which would be alpha and beta and the third a fragment homologous to portion 46 to 69 in concanavalin A. As in favin, the amino acids postulated to be involved in the formation of the hydrophobic cavity and the sugar and metal binding sites are highly conserved in L. culinaris lectin.