The pentapeptide-repeat protein, MfpA, interacts with mycobacterial DNA gyrase as a DNA T-segment mimic.
The pentapeptide-repeat protein, MfpA, interacts with mycobacterial DNA gyrase as a DNA T-segment mimic.
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DOI：
10.1073/pnas.2016705118
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发表时间：
2021-03-16
影响因子：
11.1
通讯作者：
Maxwell A
中科院分区：
文献类型：
--
作者：
Feng L;Mundy JEA;Stevenson CEM;Mitchenall LA;Lawson DM;Mi K;Maxwell A
五肽重复序列蛋白，如MfpA和Qnr蛋白，具有有趣的右手四边形β-螺旋折叠，其产生类似于双链DNA螺旋形状的细长的大致圆柱形结构。据推测，这些蛋白质，特别是那些与细菌DNA促旋酶相互作用的蛋白质，充当DNA模拟物，与DNA竞争以实现其功能。到目前为止，还没有直接的证据证明这一点。使用酶学和X-射线晶体学，我们发现分枝杆菌MfpA似乎作为一个模拟的运输（T）DNA片段在促旋酶超螺旋循环，保护酶从氟喹诺酮类抗生素。这些数据表明限制氟喹诺酮疗效的机制。DNA促旋酶，一种II型拓扑异构酶，通过ATP水解将负超螺旋引入DNA。高效的回旋酶靶向药物氟喹诺酮类（FQs）通过稳定DNA切割复合物（超螺旋循环中的短暂中间体）来中断回旋酶，导致双链DNA断裂。MfpA是分枝杆菌中的一种五肽重复蛋白，可保护促旋酶免受荧光定量酶的侵害，但其分子机制尚不清楚。在这里，我们表明耻垢分枝杆菌MfpA（MsMfpA）抑制负超螺旋M。在不存在FQs的情况下，MsMfpA降低了Smeggyrase（Msgyrase），而在FQs存在的情况下，MsMfpA降低了FQs诱导的DNA切割，保护酶免受这些药物的影响。MsMfpA通过与ATP酶结构域（MsGyrB 47）直接相互作用来刺激Msgyrase的ATP酶活性，这通过MsMfpA-MsGyrB 47复合物的X射线晶体学和突变分析来证实，表明MsMfpA模拟T（转运的）DNA片段。这些数据揭示了MfPA调节促旋酶活性的分子机制，并可能为其他五肽重复序列蛋白的作用提供一般的分子基础。
Pentapeptide-repeat proteins, such as MfpA and Qnr proteins, have an intriguing right-handed quadrilateral β-helical fold that gives rise to an elongated roughly cylindrical structure that resembles the shape of a double-stranded DNA helix. It has been speculated that these proteins, particularly those that interact with bacterial DNA gyrase, act as DNA mimics, competing with DNA to fulfil their functions. Until now there has been no direct evidence for this. Using enzymology and X-ray crystallography, we show the mycobacterial MfpA appears to act as a mimic of the transported (T) DNA segment during the gyrase supercoiling cycle, protecting the enzyme from fluoroquinolone antibiotics. These data suggest a mechanism to limit fluoroquinolone efficacy. DNA gyrase, a type II topoisomerase, introduces negative supercoils into DNA using ATP hydrolysis. The highly effective gyrase-targeted drugs, fluoroquinolones (FQs), interrupt gyrase by stabilizing a DNA-cleavage complex, a transient intermediate in the supercoiling cycle, leading to double-stranded DNA breaks. MfpA, a pentapeptide-repeat protein in mycobacteria, protects gyrase from FQs, but its molecular mechanism remains unknown. Here, we show that Mycobacterium smegmatis MfpA (MsMfpA) inhibits negative supercoiling by M. smegmatis gyrase (Msgyrase) in the absence of FQs, while in their presence, MsMfpA decreases FQ-induced DNA cleavage, protecting the enzyme from these drugs. MsMfpA stimulates the ATPase activity of Msgyrase by directly interacting with the ATPase domain (MsGyrB47), which was confirmed through X-ray crystallography of the MsMfpA–MsGyrB47 complex, and mutational analysis, demonstrating that MsMfpA mimics a T (transported) DNA segment. These data reveal the molecular mechanism whereby MfpA modulates the activity of gyrase and may provide a general molecular basis for the action of other pentapeptide-repeat proteins.
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影响因子：
5
作者：
Collin, Frederic;Karkare, Shantanu;Maxwell, Anthony
通讯作者：
Maxwell, Anthony
影响因子：
4.9
作者：
Hegde, Subray S.;Vetting, Matthew W.;Blanchard, John S.
通讯作者：
Blanchard, John S.
DOI：
10.1073/pnas.93.25.14416
发表时间：
1996-12-10
影响因子：
11.1
作者：
Kampranis, SC;Maxwell, A
通讯作者：
Maxwell, A
影响因子：
2.9
作者：
Bates, AD;ODea, MH;Gellert, M
通讯作者：
Gellert, M
影响因子：
64.5
作者：
KIRKEGAARD, K;WANG, JC
通讯作者：
WANG, JC