Metal-dependent allosteric activation and inhibition on the same molecular scaffold: the copper sensor CopY from Streptococcus pneumoniae.
Metal-dependent allosteric activation and inhibition on the same molecular scaffold: the copper sensor CopY from Streptococcus pneumoniae.
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金属依赖性的变构激活和对相同分子支架的抑制作用：肺炎链球菌的铜传感器拷贝。
DOI：
10.1039/c7sc04396a
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发表时间：
2018-01-07
期刊：
影响因子：
8.4
通讯作者：
Giedroc DP
中科院分区：
文献类型：
--
作者：
Glauninger H;Zhang Y;Higgins KA;Jacobs AD;Martin JE;Fu Y;Coyne Rd HJ;Bruce KE;Maroney MJ;Clemmer DE;Capdevila DA;Giedroc DP
CopY的动力学和边缘稳定性使得Zn（ii）和Cu（i）能够抑制DNA结合的变构活化。呼吸道病原体肺炎链球菌对铜（Cu）毒性的抗性由Cu特异性金属传感器CopY调节。CopY在结构上与金黄色葡萄球菌的耐药调节蛋白MecI和BlaI相关，但在其他方面的特征很差。在这里，我们采用了多管齐下的实验策略来定义Spn CopY配位化学和由Zn（ii）和Cu（i）对cop启动子DNA结合的变构激活和变构抑制的独特机制。我们表明，锌（ii）是由一个亚基桥接3S 1H 2 O配合物形成的协调Cu（i），由X-射线吸收光谱和比率脉冲烷基化质谱（rPA-MS）确定的相同的残基协调。载脂蛋白和锌结合的CopY是同源二聚体的小角X-射线散射（SAXS），然而，锌稳定的二聚体，缩小构象合奏的apo状态所揭示的离子迁移率质谱（IM-MS），并激活DNA结合在体外和细胞中。相比之下，Cu（i）利用相同的Cys对形成亚基桥接的、动力学稳定的多金属Cu·S簇（KCu 1016 M-1），其诱导超出二聚体的寡聚化，如SAXS、rPA-MS和NMR光谱所揭示的，导致DNA结合的抑制。这些研究表明，CopY采用构象选择来驱动Zn激活DNA结合，以及一种新的Cu（i）介导的组装机制，该机制通过配体交换催化的金属取代将CopY从DNA中解离，从而导致Cu抗性基因的表达。机制相似的抗生素耐药阻遏MecI和BlaI进行了讨论。
The dynamics and marginal stability of CopY enable allosteric activation of DNA binding by Zn(ii) and inhibition by Cu(i). Resistance to copper (Cu) toxicity in the respiratory pathogen Streptococcus pneumoniae is regulated by the Cu-specific metallosensor CopY. CopY is structurally related to the antibiotic-resistance regulatory proteins MecI and BlaI from Staphylococcus aureus, but is otherwise poorly characterized. Here we employ a multi-pronged experimental strategy to define the Spn CopY coordination chemistry and the unique mechanism of allosteric activation by Zn(ii) and allosteric inhibition by Cu(i) of cop promoter DNA binding. We show that Zn(ii) is coordinated by a subunit-bridging 3S 1H2O complex formed by the same residues that coordinate Cu(i), as determined by X-ray absorption spectroscopy and ratiometric pulsed alkylation-mass spectrometry (rPA-MS). Apo- and Zn-bound CopY are homodimers by small angle X-ray scattering (SAXS); however, Zn stabilizes the dimer, narrows the conformational ensemble of the apo-state as revealed by ion mobility-mass spectroscopy (IM-MS), and activates DNA binding in vitro and in cells. In contrast, Cu(i) employs the same Cys pair to form a subunit-bridging, kinetically stable, multi-metallic Cu·S cluster (KCu ≈ 1016 M–1) that induces oligomerization beyond the dimer as revealed by SAXS, rPA-MS and NMR spectroscopy, leading to inhibition of DNA binding. These studies suggest that CopY employs conformational selection to drive Zn-activation of DNA binding, and a novel Cu(i)-mediated assembly mechanism that dissociates CopY from the DNA via ligand exchange-catalyzed metal substitution, leading to expression of Cu resistance genes. Mechanistic parallels to antibiotic resistance repressors MecI and BlaI are discussed.
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影响因子：
14.8
作者：
Fu, Yue;Tsui, Ho-Ching Tiffany;Bruce, Kevin E.;Sham, Lok-To;Higgins, Khadine A.;Lisher, John P.;Kazmierczak, Krystyna M.;Maroney, Michael J.;Dann, Charles E., III;Winkler, Malcolm E.;Giedroc, David P.
通讯作者：
Giedroc, David P.
影响因子：
6.4
作者：
Capdevila DA;Edmonds KA;Giedroc DP
通讯作者：
Giedroc DP
影响因子：
2.9
作者：
Apuy, JL;Chen, XH;Giedroc, DP
通讯作者：
Giedroc, DP
影响因子：
2.9
作者：
Apuy, JL;Busenlehner, LS;Giedroc, DP
通讯作者：
Giedroc, DP
影响因子：
4.1
作者：
Cantini, Francesca;Banci, Lucia;Solioz, Marc
通讯作者：
Solioz, Marc