Crystal structure and conformational stability of a galectin-1 tandem-repeat mutant with a short linker
Crystal structure and conformational stability of a galectin-1 tandem-repeat mutant with a short linker
复制标题
具有短接头的半乳糖凝集素-1串联重复突变体的晶体结构和构象稳定性
DOI：
10.1093/glycob/cwab101
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发表时间：
2022
期刊：
影响因子：
4.3
通讯作者：
Takanori Nakamura
中科院分区：
文献类型：
--
作者：
Yasuhiro Nonaka;Takashi Ogawa;Hiroki Shoji;Nozomu Nishi;Shigehiro Kamitori;Takanori Nakamura
半乳糖凝集素的结构域结构的修改已被尝试分析其生物学功能和开发医疗应用。先前报道了几种类型的半乳糖凝集素-1重复突变体，但是，不清楚野生型的天然结构是否被保留。在这项研究中，我们确定了一个半乳糖凝集素-1的串联重复突变体的晶体结构与一个短的连接肽，并比较了野生型和突变体的化学变性的解折叠配置文件。突变体的结构与野生型的二聚体的结构一致，并且保留了两个碳水化合物结合位点。野生型与乳糖的解折叠曲线表明，二聚体解离和三级结构解折叠是伴随着微摩尔蛋白浓度。野生型的中点变性剂浓度依赖于蛋白质浓度，并且低于突变体。连接两个亚基显着稳定的三级结构。突变体表现出更高的T细胞生长抑制活性和相当的血凝活性。结构稳定可以防止内部半胱氨酸残基的氧化。
Modification of the domain architecture of galectins has been attempted to analyze their biological functions and to develop medical applications. Several types of galectin-1 repeat mutants were previously reported but, however, it was not clear whether the native structure of the wild type was retained. In this study, we determined the crystal structure of a galectin-1 tandem-repeat mutant with a short linker peptide, and compared the unfolding profiles of the wild type and mutant by chemical denaturation. The structure of the mutant was consistent with that of the dimer of the wild type, and both carbohydrate-binding sites were retained. The unfolding curve of the wild type with lactose suggested that the dimer dissociation and the tertiary structure unfolding was concomitant at micromolar protein concentrations. The midpoint denaturant concentration of the wild type was dependent on the protein concentration and lower than that of the mutant. Linking the two subunits significantly stabilized the tertiary structure. The mutant exhibited higher T-cell growth-inhibition activity and comparable hemagglutinating activity. Structural stabilization may prevent the oxidation of the internal cysteine residue.