The effect of genome length on ejection forces in bacteriophage lambda
The effect of genome length on ejection forces in bacteriophage lambda
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DOI：
10.1016/j.virol.2006.01.003
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发表时间：
2006-05-10
期刊：
影响因子：
3.7
通讯作者：
Phillips, R
中科院分区：
文献类型：
--
作者：
Grayson, P;Evilevitch, A;Phillips, R
各种病毒将它们的遗传物质紧密地包装在蛋白质衣壳中，这些衣壳几乎不足以包裹基因组。特别是，在噬菌体中，在包装和弹出过程中会遇到高达60 pN的力，这是由DNA弯曲弹性和自相互作用产生的。高的力量被认为是重要的弹射过程，虽然他们的参与程度尚不清楚。因此，有必要定量模型和实验，揭示有关的DNA弹射力的性质，在这里，我们报告的两个不同的突变体的噬菌体λ，λ b221cI26和λ cI60，其基因组长度的差异相似的30%的弹射力的测量。正如预期的力驱动的弹射机制，DNA释放被完全抑制的渗透压随基因组长度而变化：我们发现抑制压力为15大气压和25大气压，分别为短和长的基因组，值与我们的理论计算一致。(c)2006年爱思唯尔公司All rights reserved.
A variety of viruses tightly pack their genetic material into protein capsids that are barely large enough to enclose the genome. In particular, in bacteriophages, forces as high as 60 pN are encountered during packaging and ejection, produced by DNA bending elasticity and self-interactions. The high forces are believed to be important for the ejection process, though the extent of their involvement is not yet clear. As a result, there is a need for quantitative models and experiments that reveal the nature of the forces relevant to DNA ejection, Here, we report measurements of the ejection forces for two different mutants of bacteriophage lambda, lambda b221cI26 and lambda cI60, which differ in genome length by similar to 30%. As expected for a force-driven ejection mechanism, the osmotic pressure at which DNA release is completely inhibited varies with the genome length: we find inhibition pressures of 15 atm and 25 atm, for the short and long genomes, respectively, values that are in agreement with our theoretical calculations. (c) 2006 Elsevier Inc. All rights reserved.