Decorin is a Zn2+ metalloprotein.
Decorin is a Zn2+ metalloprotein.
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核心蛋白聚糖是一种 Zn2 金属蛋白。
DOI：
10.1074/jbc.274.18.12454
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Höök,M
中科院分区：
文献类型：
--
作者：
Yang,VW;LaBrenz,SR;Rosenberg,LC;McQuillan,D;Höök,M
核心蛋白聚糖广泛分布于哺乳动物的细胞外基质中，是蛋白聚糖家族的一员，其特征在于由富含亮氨酸的重复基序主导的核心蛋白。我们在这里表明，核心蛋白聚糖提取牛组织变性条件下或生产的重组“天然”形式的培养的哺乳动物细胞具有高亲和力的Zn 2+所证明的平衡透析。Zn 2+结合位点位于核心蛋白的N-末端结构域，其含有4个Cys残基，间隔让人想起锌指。核心蛋白聚糖的N-末端结构域是一个41个氨基酸的重组肽，具有完全的锌离子结合活性，结合两个锌离子的平均KD为3 × 10− 7 m。Zn 2+与该肽的结合导致二级结构的变化，如圆二色性光谱所示。双糖蛋白聚糖，一种结构上与核心蛋白聚糖密切相关的蛋白聚糖，含有类似的高亲和力Zn 2+结合片段，而结构上更远相关的蛋白聚糖，骨骺蛋白聚糖和骨聚糖，不以高亲和力结合Zn 2+。
Decorin is ubiquitously distributed in the extracellular matrix of mammals and a member of the proteoglycan family characterized by a core protein dominated by leucine-rich repeat motifs. We show here that decorin extracted from bovine tissues under denaturing conditions or produced in recombinant “native” form by cultured mammalian cells has a high affinity for Zn2+as demonstrated by equilibrium dialyses. The Zn2+-binding sites are localized to the N-terminal domain of the core protein that contains 4 Cys residues in a spacing reminiscent of a zinc finger. A recombinant 41-amino acid long peptide representing the N-terminal domain of decorin has full Zn2+binding activity and binds two Zn2+ions with an averageKDof 3 × 10−7m. Binding of Zn2+to this peptide results in a change in secondary structure as shown by circular dichroism spectroscopy. Biglycan, a proteoglycan that is structurally closely related to decorin contains a similar high affinity Zn2+-binding segment, whereas the structurally more distantly related proteoglycans, epiphycan and osteoglycin, do not bind Zn2+with high affinity.