Preheating induced homogeneity of the small heat shock protein from Methanococcus jannaschii.
Preheating induced homogeneity of the small heat shock protein from Methanococcus jannaschii.
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DOI：
10.1016/j.bbapap.2007.12.008
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发表时间：
2008-03
期刊：
影响因子：
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通讯作者：
Aoneng Cao;Z. Wang;P. Wei;Fei Xu;Jie Cao;L. Lai
中科院分区：
文献类型：
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作者：
Aoneng Cao;Z. Wang;P. Wei;Fei Xu;Jie Cao;L. Lai
小的热休克蛋白通常在高温或预热后表现出增加的伴侣样活性。然而，其激活机制尚不清楚。本研究采用多种生物物理方法研究了Mj HSP16.5的预热活化过程。虽然有报道称Mj HSP16.5是单分散程度最高的sHSPs，但我们发现新纯化的Mj HSP16.5实际上是异质的。85℃预热可以激活Mj HSP16.5，同时使其变成更致密的均质物质。预热后不同的冷却速率对Mj HSP16.5活性没有影响，说明85℃预热Mj HSP16.5处于最活跃也是最稳定的状态。这些结果表明，Mj HSP16.5的激活过程可能伴随着一个重折叠过程。
Small heat shock proteins usually exhibit increased chaperone-like activity either at high temperatures or after preheating. However, the activation mechanism is still unclear. In the current study, we investigated the preheating-activation process of Mj HSP16.5, using various biophysical methods. Although Mj HSP16.5 was reported to be the most monodispersed sHSPs, we found that the newly purified Mj HSP16.5 was actually heterogeneous. 85 °C-preheating could activate Mj HSP16.5 and turn it into a more compact homogeneous species at the same time. Different cooling rates after preheating did not change the activity of Mj HSP16.5, suggesting that the 85 °C-preheated Mj HSP16.5 is in the most active and also the most stable state. These results demonstrate that the activation process of Mj HSP16.5 might accompany a refolding process.