Trans cooperativity by a split DNA recombinase: the central and catalytic domains of bacteriophage lambda integrase cooperate in cleaving DNA substrates when the two domains are not covalently linked.
Trans cooperativity by a split DNA recombinase: the central and catalytic domains of bacteriophage lambda integrase cooperate in cleaving DNA substrates when the two domains are not covalently linked.
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裂解 DNA 重组酶的反式协同作用：当两个结构域未共价连接时，噬菌体 lambda 整合酶的中心结构域和催化结构域协同裂解 DNA 底物。
DOI：
10.1016/j.jmb.2007.04.024
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发表时间：
2007
影响因子：
5.6
通讯作者：
Foster,MarkP
中科院分区：
文献类型：
--
作者：
Subramaniam,Srisunder;Kamadurai,HariB;Foster,MarkP
λ整合酶家族的位点特异性重组酶通过c端催化结构域和灵活连接的“核心结合”结构域与DNA底物的两侧合作结合，识别和切割同源DNA位点；这种解理的调节是通过形成高阶配合物来实现的。我们报道了λ-整合酶的核心结合结构域能够刺激催化结构域的活性，即使两个结构域没有连接。这种反式刺激在没有显著增加催化结构域对其DNA底物的亲和力的情况下完成。此外，我们发现DNA底物的突变可以消除这种影响，同时保留切割的特异性决定因素。由于这些结构域并不直接相互作用，这一发现意味着反式激活是通过DNA底物实现的，在这种和类似的DNA结合和切割酶中可能具有重要的机械作用。
Site-specific recombinases of the λ-integrase family recognize and cleave their cognate DNA sites through cooperative binding to opposite sides of the DNA substrate by a C-terminal catalytic domain and a flexibly linked “core-binding” domain; regulation of this cleavage is achieved via the formation of higher-order complexes. We report that the core-binding domain of λ-integrase is able to stimulate the activity of the catalytic domain even when the two domains are not linked. This trans stimulation is accomplished without significantly increasing the affinity of the catalytic domain for its DNA substrate. Moreover, we show that mutations in the DNA substrate can abrogate this effect while retaining specificity determinants for cleavage. Since the domains do not significantly interact directly, this finding implies that trans activation is achieved via the DNA substrate in a manner that may be mechanistically important in this and similar DNA binding and cleaving enzymes.