A lower-order oligomer form of phage shock protein A (PspA) stably associates with the hexameric AAA(+) transcription activator protein PspF for negative regulation.
A lower-order oligomer form of phage shock protein A (PspA) stably associates with the hexameric AAA(+) transcription activator protein PspF for negative regulation.
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DOI：
10.1016/j.jmb.2009.09.055
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发表时间：
2009-12-11
影响因子：
5.6
通讯作者：
Buck M
中科院分区：
文献类型：
--
作者：
Joly N;Burrows PC;Engl C;Jovanovic G;Buck M
为了在不同的环境中生存和定居，包括感染期间使用的环境，细菌已经开发了各种适应系统。其中包括噬菌体休克蛋白(PSP)反应，这种反应可以在大肠杆菌中被丝状噬菌体感染(特别是噬菌体分泌素PIV)和其他膜损害剂诱导。大肠杆菌PSP系统由7种蛋白质组成，其中PSPA是核心成分。PSPA是一种双功能蛋白，它直接参与(I)PSP特异性转录激活因子PspF的负调控和(Ii)维持膜完整性的机制，该机制涉及36-聚环复合体的形成。在此，我们证实PSPA对PspF-ATPase活性的负调节是协同抑制的结果。我们提供的生化证据表明，一个抑制性的PSPA-PspF调节复合体，它显著降低了PspF ATPase的活性，由大约6个PspF亚基和6个PSPA亚基组成，这表明PSPA至少存在于两个不同的寡聚体组装中。我们现在确定PSPA的所有四个假定的螺旋结构域对36-mer的形成都是关键的。相反，并不是所有的四个螺旋结构域都是形成抑制性PSPA-PspF复合体所必需的。由于一系列初始PspF低聚态允许形成表面上的PSPA-PspF十二聚体组装，我们得出结论，PSPA和PspF显示出强烈的自组装成单一定义的异构体调节复合体的倾向。
To survive and colonise their various environments, including those used during infection, bacteria have developed a variety of adaptive systems. Amongst these is phage shock protein (Psp) response, which can be induced in Escherichia coli upon filamentous phage infection (specifically phage secretin pIV) and by other membrane-damaging agents. The E. coli Psp system comprises seven proteins, of which PspA is the central component. PspA is a bifunctional protein that is directly involved in (i) the negative regulation of the psp-specific transcriptional activator PspF and (ii) the maintenance of membrane integrity in a mechanism proposed to involve the formation of a 36-mer ring complex. Here we established that the PspA negative regulation of PspF ATPase activity is the result of a cooperative inhibition. We present biochemical evidence showing that an inhibitory PspA–PspF regulatory complex, which has significantly reduced PspF ATPase activity, is composed of around six PspF subunits and six PspA subunits, suggesting that PspA exists in at least two different oligomeric assemblies. We now establish that all four putative helical domains of PspA are critical for the formation of the 36-mer. In contrast, not all four helical domains are required for the formation of the inhibitory PspA–PspF complex. Since a range of initial PspF oligomeric states permit formation of the apparent PspA–PspF dodecameric assembly, we conclude that PspA and PspF demonstrate a strong propensity to self-assemble into a single defined heteromeric regulatory complex.
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DOI：
10.1126/science.1105932
发表时间：
2005-03-25
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Rappas M;Schumacher J;Beuron F;Niwa H;Bordes P;Wigneshweraraj S;Keetch CA;Robinson CV;Buck M;Zhang X
通讯作者：
Zhang X
影响因子：
3.2
作者：
Jovanovic, G;Dworkin, J;Model, P
通讯作者：
Model, P
影响因子：
3.2
作者：
Vrancken, Kristof;Van Mellaert, Lieve;Anne, Jozef
通讯作者：
Anne, Jozef
影响因子：
11.4
作者：
Kleerebezem, M;Crielaard, W;Tommassen, J
通讯作者：
Tommassen, J
影响因子：
5.6
作者：
BRISSETTE, JL;WEINER, L;MODEL, P
通讯作者：
MODEL, P