The use of high hydrostatic pressure to investigate structure–function relationships in biomacromolecules in solution provides precise information about conformational changes and variations of the interactions between these macromolecules and the solvent, as well as the volume changes associated with their activity. The complementary use of osmotic pressure reveals quantitatively the extent and direction of the water exchanges between the macromolecules and the solvent and the number of water molecules involved in these exchanges. In this review, the chemistry of ribozymes and the influence of pressure is described. In the case of the hairpin ribozyme, pressure slowed down the self-cleavage reaction on the basis that the formation of the transition state involves a positive ΔV^⧧ of activation and the release of 78 ± 4 water molecules. The self-cleaving activity of the hammerhead ribozyme is also slowed down by pressure on the basis of kinetic parameters and ΔVs comparable to those of the hairpin ribozymes. However, it appears that the solution of the hammerhead ribozyme used in this study contains two populations of molecules which differ by the values of these parameters. The results obtained in the case of small self-cleaving ribozymes containing adenine bulges are consistent with the hypothesis that these small RNAs that bind amino acids or peptides could have appeared in prebiotic chemistry under extreme conditions in deep-sea vents or hydrothermal surface sites.

中文翻译：

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核酶化学：处于或不处于高压下。

使用高静水压力研究溶液中生物大分子的结构-功能关系可提供有关这些高分子与溶剂之间相互作用的构象变化和变化以及与它们的活性相关的体积变化的精确信息。渗透压的互补使用定量地揭示了大分子与溶剂之间的水交换的程度和方向以及参与这些交换的水分子的数量。在这篇综述中，描述了核酶的化学性质和压力的影响。在发夹状核酶的情况下，由于过渡态的形成涉及一个正的ΔV ^pressure，压力减慢了自身裂解反应。活化和释放78±4个水分子。锤头状核酶的自切割活性也动力学参数和Δ的基础上减慢通过压力V比较的，比得上那些发夹核酶。但是，似乎这项研究中使用的锤头状核酶溶液包含两个分子种群，这些分子种群的参数值不同。在含有腺嘌呤凸起的小分子自切割核酶的情况下获得的结果与以下假设相一致：这些氨基酸或多肽的小RNA在极端条件下的深海通风口或热液表面部位可能已出现在益生元化学中。