A widespread bacteriophage abortive infection system functions through a Type IV toxin-antitoxin mechanism.
A widespread bacteriophage abortive infection system functions through a Type IV toxin-antitoxin mechanism.
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广泛的噬菌体流产感染系统通过IV型毒素 - 抗毒素机制发挥作用。
DOI：
10.1093/nar/gkt1419
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发表时间：
2014-04
影响因子：
14.9
通讯作者：
Fineran PC
中科院分区：
文献类型：
--
作者：
Dy RL;Przybilski R;Semeijn K;Salmond GP;Fineran PC
细菌败育感染（Abi）系统是由噬菌体感染激活并限制病毒复制的“利他”细胞死亡系统，从而为细菌群体提供保护。在这里，我们使用了一种新的方法，筛选阿比特龙系统作为一种工具，以确定和表征毒素-抗毒素（TA）的作用阿比特龙系统。我们发现，AbiE系统编码的双顺反子操纵子和功能通过非相互作用（IV型）抑菌TA机制。abiE操纵子是负自动调节的抗毒素，AbiEi，一个广泛的家庭成员的假定的转录调节。AbiEi具有抑制abiE转录所需的N-末端翼状螺旋-转角螺旋结构域，和未表征的双功能C-末端结构域，其是转录抑制所必需的并且足以中和毒素。同源毒素AbiEii是一种预测的核苷酸转移酶（NTase），是DNA聚合酶β家族的成员。AbiEii特异性结合GTP，保守的NTase基序（I-III）和新鉴定的基序（IV）中的突变消除了GTP结合和随后的毒性。AbiE系统可以提供噬菌体抗性并使移动的遗传元件（例如质粒）稳定化。我们的研究揭示了广泛的双功能AbiE Abi-TA系统的调节和功能以及毒素和抗毒素蛋白的生化特性的分子见解。
Bacterial abortive infection (Abi) systems are ‘altruistic’ cell death systems that are activated by phage infection and limit viral replication, thereby providing protection to the bacterial population. Here, we have used a novel approach of screening Abi systems as a tool to identify and characterize toxin–antitoxin (TA)-acting Abi systems. We show that AbiE systems are encoded by bicistronic operons and function via a non-interacting (Type IV) bacteriostatic TA mechanism. The abiE operon was negatively autoregulated by the antitoxin, AbiEi, a member of a widespread family of putative transcriptional regulators. AbiEi has an N-terminal winged-helix-turn-helix domain that is required for repression of abiE transcription, and an uncharacterized bi-functional C-terminal domain, which is necessary for transcriptional repression and sufficient for toxin neutralization. The cognate toxin, AbiEii, is a predicted nucleotidyltransferase (NTase) and member of the DNA polymerase β family. AbiEii specifically bound GTP, and mutations in conserved NTase motifs (I-III) and a newly identified motif (IV), abolished GTP binding and subsequent toxicity. The AbiE systems can provide phage resistance and enable stabilization of mobile genetic elements, such as plasmids. Our study reveals molecular insights into the regulation and function of the widespread bi-functional AbiE Abi-TA systems and the biochemical properties of both toxin and antitoxin proteins.
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影响因子：
14.9
作者：
Fozo EM;Makarova KS;Shabalina SA;Yutin N;Koonin EV;Storz G
通讯作者：
Storz G
影响因子：
3.2
作者：
Bouchard, JD;Dion, E;Moineau, S
通讯作者：
Moineau, S
DOI：
10.1073/pnas.0808832106
发表时间：
2009-01-20
影响因子：
11.1
作者：
Fineran, Peter C.;Blower, Tim R.;Salmond, George P. C.
通讯作者：
Salmond, George P. C.
影响因子：
4.4
作者：
Garvey, P;Rince, A;Fitzgerald, GF
通讯作者：
Fitzgerald, GF
DOI：
10.1007/s10969-009-9060-4
发表时间：
2009-04
期刊：
Journal of structural and functional genomics
影响因子：
--
作者：
Janowski, Robert;Panjikar, Santosh;Eddine, Ali Nasser;Kaufmann, Stefan H E;Weiss, Manfred S
通讯作者：
Weiss, Manfred S