来自Azotobacter vinelandii的化酶铁蛋白的晶体结构
M M Georgiadis1, H Komiya, P Chakrabarti
1Department of Biochemistry, Columbia University, New York, NY 10032.
概括
酶Fe-蛋白结构显示,腺三酸盐 (ATP) 的水解通过异质变化间接与电子转移相结合. 这一发现为固和其他能量转换系统提供了洞察力.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 固定的方法是固定.
背景情况:
- 基酶促进了依赖ATP的固,将二转化为氨.
- 它包括Fe-蛋白和MoFe-蛋白;Fe-蛋白将ATP水解与电子转移联系起来.
研究的目的:
- 通过确定Azotobacter vinelandii化酶Fe-蛋白的晶体结构来阐明ATP在固中的作用.
- 了解核酸水解和电子转移之间的合机制.
主要方法:
- 使用X射线晶体学来确定酶Fe-蛋白的结构.
- 该结构的分辨率为2.9安格斯特罗姆分辨率.
主要成果:
- 铁蛋白是一种二元体,其中有一个中心的4Fe:4S集群,由两个子单元的半氨酸结合在一起.
- 一个单一的腺二酸盐 (ADP) 分子在子单元接口上结合,距离4Fe:4S集群约20A.
- 在ATP水解和电子转移之间直接合不太可能;建议间接合.
结论:
- 该结构表明核酸水解和Fe-蛋白中的电子转移之间的间接合.
- 这种机制与H-Ras p21和recA蛋白质有相似之处.
- 铁蛋白结构可能有助于研究其他核酸结合,能量转导系统.
相关概念视频
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Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
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Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme can...
A protein's shape is critical to its function. For example, an enzyme can...
Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
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The primary structure of a protein is its amino acid sequence.
The primary structure of a protein is its amino acid sequence.
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