Phospholipids promote dissociation of ADP from the Mycobacterium avium DnaA protein.
Phospholipids promote dissociation of ADP from the Mycobacterium avium DnaA protein.
复制标题
磷脂促进 ADP 从鸟分枝杆菌 DnaA 蛋白上解离。
DOI：
10.1093/oxfordjournals.jbchem.a003091
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发表时间：
2002
影响因子：
2.7
通讯作者：
Madiraju,Murty
中科院分区：
文献类型：
--
作者：
Yamamoto,Kohji;Rajagopalan,Malini;Madiraju,Murty
鸟支原体 DnaA 蛋白是大肠杆菌复制起始蛋白的对应物，在带有 N 末端组氨酸标签的大肠杆菌中过量产生，并在镍亲和柱上纯化至均质。重组DnaA蛋白以高亲和力结合ATP和ADP，并表现出弱的ATP酶活性。 ATP 水解后，ADP 仍与蛋白质牢固结合，并且发现 ATP 与结合的 ADP 的交换很弱。酸性磷脂（例如磷脂酰肌醇、磷脂酰甘油和心磷脂）促进 ADP 从 DnaA 蛋白上解离，而中性磷脂（磷脂酰乙醇胺）则不然。在鸟分枝杆菌复制起点的存在下，磷脂促进了 ADP 从 DnaA 蛋白的解离。我们认为鸟分枝杆菌中 DNA 复制的起始涉及 DnaA、腺嘌呤核苷酸和磷脂之间的相互作用。
, M. avium DnaA protei n, the counterpart of Escherichia coli replication initiator protein, was overproduced i n E. coli with an N-terminal histidine tag and purified to homogeneity on a nickel affin ity column. The recombinant DnaA protein bound both ATP and ADP with high affinity and showed a weak ATPase activity. ADP, following the hydrolysis of ATP, remained b ound to the protein strongly and the exchange of ATP for bound ADP was found to be weak. Acidic phopsholipids such as phosphatidylinositol, phosphatidylglycerol, and cardi olipin, promoted the dissociation of ADP from the DnaA protein, whereas the neutral phospholipid, phosphatidylethanolamine, did not. The phospholipid promoted dissocia tion of ADP from DnaA protein was stimulated in the presence of the M. avium origin of replication. We suggest that the initiation of DNA replication in M. avium involves an interplay among DnaA, adenine nucleotides and phospholipids.