Membrane attachment activates dnaA protein, the initiation protein of chromosome replication in Escherichia coli.
Membrane attachment activates dnaA protein, the initiation protein of chromosome replication in Escherichia coli.
复制标题
膜附着激活 dnaA 蛋白，这是大肠杆菌中染色体复制的起始蛋白。
DOI：
10.1073/pnas.85.19.7202
复制
发表时间：
1988
影响因子：
11.1
通讯作者：
Kornberg,A
中科院分区：
文献类型：
--
作者：
Yung,BY;Kornberg,A
ADP和ATP与dnaA蛋白紧密结合，并且对其在DNA复制中的功能至关重要;这些核苷酸的交换受到大肠杆菌膜中存在的酸性磷脂（心磷脂和磷脂酰甘油）的特异性影响[Sekimizu，K. & Kornberg，A.（1988）J.Biol.Chem.263，7131-7135]。我们现在发现来源于缺乏不饱和脂肪酸的膜的磷脂（例如，油酸）不能促进交换。这一观察结果与3-癸炔酰基-N-乙酰半胱胺的长期已知作用显著相关，3-癸炔酰基-N-乙酰半胱胺是一种“自杀类似物”，可阻止大肠杆菌复制周期的启动。通过抑制油酸的合成来抑制大肠杆菌，这种抑制可以通过向细胞提供油酸来克服。温度、不饱和脂肪酸含量和胆固醇含量对dnaA蛋白与磷脂特异性结合的深远影响可以通过磷脂需要处于液相囊泡中来解释。这些结果表明，dnaA蛋白的膜附着是至关重要的，它的功能，在启动染色体复制在E。杆菌
ADP and ATP are tightly bound to dnaA protein and are crucial to its function in DNA replication; the exchange of these nucleotides is effected specifically by the acidic phospholipids (cardiolipin and phosphatidylglycerol) present in Escherichia coli membranes [Sekimizu, K. & Kornberg, A. (1988) J. Biol. Chem. 263, 7131-7135]. We now find that phospholipids derived from membranes lacking an unsaturated fatty acid (e.g., oleic acid) are unable to promote the exchange. This observation correlates strikingly with the long-known effect of 3-decynoyl-N-acetylcysteamine, a "suicide analog" that prevents initiation of a cycle of replication in E. coli by inhibiting the synthesis of oleic acid, an inhibition that can be overcome by providing the cells with oleic acid. Profound influences on the specific binding of dnaA protein to phospholipids by temperature, the content of unsaturated fatty acids, and the inclusion of cholesterol can be explained by the need for the phospholipids to be in fluid-phase vesicles. These findings suggest that membrane attachment of dnaA protein is vital for its function in the initiation of chromosome replication in E. coli.