Binding of adenine and adenine-related compounds to the clay montmorillonite and the mineral hydroxylapatite
Binding of adenine and adenine-related compounds to the clay montmorillonite and the mineral hydroxylapatite
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腺嘌呤和腺嘌呤相关化合物与粘土蒙脱石和矿物羟基磷灰石的结合
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
G. Zubay
中科院分区：
文献类型：
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作者：
D. Winter;G. Zubay
第一批生物可能仅由结合在矿物颗粒表面的 RNA 或类似 RNA 的分子组成。该理论的一个关键方面是这些矿物质颗粒具有 RNA 及其益生元前体的结合位点。本研究的目的是探索蒙脱石和羟基磷灰石这两种研究最充分的矿物质对于 RNA 可能前体的结合特性。研究的化合物包括嘌呤、嘧啶、核苷、核苷酸、核苷酸辅酶、二氨基马来腈和氨基咪唑甲酰胺。羟基磷灰石的亲和力主要由带负电的小分子和矿物中带正电的位点之间的离子相互作用决定。与蒙脱石的结合呈现出更复杂的情况。这些粘土颗粒对有机环结构具有高亲和力，如果它们带正电，这种亲和力就会增强。这种结合可能发生在这些片状粘土颗粒的带负电的面上。这些片材边缘上的附加结合位点对带负电的分子具有中等亲和力。与这些矿物质结合的小分子有时独立地结合到矿物质上的位点，有时与结合分子之间有利的相互作用协同结合。
The first living things may have consisted of no more than RNA or RNA-like molecules bound to the surfaces of mineral particles. A key aspect of this theory is that these mineral particles have binding sites for RNA and its prebiotic precursors. The object of this study is to explore the binding properties of two of the best studied minerals, montmorillonite and hydroxylapatite, for possible precursors of RNA. The list of compounds investigated includes purines, pyrimidines, nucleosides, nucleotides, nucleotide coenzymes, diaminomaleonitrile and aminoimidazole carbox-amide. Affinities for hydroxylapatite are dominated by ionic interactions between negatively charged small molecules and positively charged sites in the mineral. Binding to montmorillonite presents a more complex picture. These clay particles have a high affinity for organic ring structures which is augmented if they are positively charged. This binding probably takes place on the negatively charged faces of these sheet-like clay particles. Additional binding sites on the edges of of these sheets have a moderate affinity for negatively charged molecules.Small molecules that bind to these minerals sometimes bind independently to sites on the minerals and sometimes bind cooperatively with favorable interactions between the bound molecules.