In this study, the SCRM-1 gene from Caenorhabditis elegans was cloned and overexpressed in E. coli to study the biochemical properties of scramblase. This is the first report showing that this scramblase from C. elegans possesses a Ca2+-dependent and head group-independent scramblase activity. The SCRM-1 of C.elegans possesses functional domains including a single EF-hand-like Ca2+ binding domain, as human scramblases do. A point mutation in the EF-hand-like Ca2+ binding motif results in loss of scramblase activity. Other biochemical assays like carbocyanine staining, Tb3+ luminescence, Tryptophan fluorescence, and CD spectroscopy strongly proved the role of the EF-hand motif for functional activity. The increase in protein size in solution upon incubating with Ca2+ shows ligand-dependent oligomerization and conformational changes.

中文翻译：

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秀丽隐杆线虫的磷脂加扰酶SCRM-1的分子克隆和生化特性。

在这项研究中，秀丽隐杆线虫的SCRM-1基因被克隆并在大肠杆菌中过表达，以研究scramblase的生化特性。这是第一个报道，表明秀丽隐杆线虫的这种乱序酶具有Ca2 +依赖性和头基依赖性的乱序酶活性。秀丽隐杆线虫的SCRM-1拥有功能域，包括单个EF手状Ca2 +结合域，就像人类的scramblases一样。EF手样Ca2 +结合基序中的点突变导致乱序酶活性丧失。其他生化分析，例如碳花青染色，Tb3 +发光，色氨酸荧光和CD光谱，强烈证明了EF手基序对功能活性的作用。与Ca2 +孵育后溶液中蛋白质大小的增加显示配体依赖性寡聚和构象变化。