Assembly properties of bacterial tubulin homolog FtsZ regulated by the positive regulator protein ZipA and ZapA from Pseudomonas aeruginosa.
Assembly properties of bacterial tubulin homolog FtsZ regulated by the positive regulator protein ZipA and ZapA from Pseudomonas aeruginosa.
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DOI：
10.1038/s41598-020-78431-x
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发表时间：
2020-12-07
影响因子：
4.6
通讯作者：
Chen Y
中科院分区：
文献类型：
--
作者：
Rahman MU;Li Z;Zhang T;Du S;Ma X;Wang P;Chen Y
细菌微管蛋白同源物FtsZ自组装成动态原丝，其形成收缩环（Z环）的支架以实现细菌细胞分裂。在这里，我们研究了铜绿假单胞菌（PaFtsZ）的生化特性及其两个正调节蛋白，ZipA和ZapA的影响。与大肠杆菌FtsZ相似，PaFtsZ具有较强的GTP酶活性，在pH 7.5时约为7.8 GTP min-1 FtsZ-1，并在体外组装成主要为短的单丝。而在pH7.5溶液中，PaFtsZ原丝为直丝和“中间弯曲”（直径100-300 nm）的混合物，在pH6.5溶液中，PaFtsZ原丝形成一些纤维束。ZipA对PaFtsZ组装的影响随pH的变化而变化，在pH6.5的缓冲液中，ZipA诱导PaFtsZ形成大束。在pH 7.5的缓冲液中，PaFtsZ-ZipA原丝不成束，但ZipA增强PaFtsZ组装并促进更多弯曲的丝。与来自其他细菌物种的ZapA相比，来自铜绿假单胞菌的ZapA在pH 6.5和pH 7.5下均诱导PaFtsZ原丝缔合成长直的松散束和/或片，这对PaFtsZ的GTdR活性几乎没有影响。这些结果为我们提供了进一步的信息，ZipA作为FtsZ弯曲丝的增强剂，而ZapA作为FtsZ直丝的稳定剂。
Bacterial tubulin homolog FtsZ self-assembles into dynamic protofilaments, which forms the scaffold for the contractile ring (Z-ring) to achieve bacterial cell division. Here, we study the biochemical properties of FtsZ from Pseudomonas aeruginosa (PaFtsZ) and the effects of its two positive regulator proteins, ZipA and ZapA. Similar to Escherichia coli FtsZ, PaFtsZ had a strong GTPase activity, ~ 7.8 GTP min-1 FtsZ-1 at pH 7.5, and assembled into mainly short single filaments in vitro. However, PaFtsZ protofilaments were mixtures of straight and “intermediate-curved” (100–300 nm diameter) in pH 7.5 solution and formed some bundles in pH 6.5 solution. The effects of ZipA on PaFtsZ assembly varied with pH. In pH 6.5 buffer ZipA induced PaFtsZ to form large bundles. In pH 7.5 buffer PaFtsZ-ZipA protofilaments were not bundled, but ZipA enhanced PaFtsZ assembly and promoted more curved filaments. Comparable to ZapA from other bacterial species, ZapA from P. aeruginosa induced PaFtsZ protofilaments to associate into long straight loose bundles and/or sheets at both pH 6.5 and pH 7.5, which had little effect on the GTPase activity of PaFtsZ. These results provide us further information that ZipA functions as an enhancer of FtsZ curved filaments, while ZapA works as a stabilizer of FtsZ straight filaments.