Cueto-Díaz Eduardo J, Gálvez-Martínez Santos, Colin-García María, Mateo-Martí Eva
Centro de Astrobiología (CSIC-INTA), Ctra. Ajalvir, km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.
Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico.
Life (Basel). 2023 Mar 30;13(4):908. doi: 10.3390/life13040908.
The role of minerals in the origin of life and prebiotic evolution remains unknown and controversial. Mineral surfaces have the potential to facilitate prebiotic polymerization due to their ability to adsorb and concentrate biomolecules that subsequently can catalyse reactions; however, the precise nature of the interaction between the mineral host and the guest biomolecule still needs to be understood. In this context, we spectroscopically characterized, using infrared, X-ray photoemission spectroscopy (XPS) and X-ray diffraction (XRD) techniques, the interaction between L-proline and montmorillonite, olivine, iron disulphide, and haematite (minerals of prebiotic interest), by evaluating their interaction from a liquid medium. This work provides insight into the chemical processes occurring between proline, the only cyclic amino acid, and this selection of minerals, each of them bearing a particular chemical and crystal structures. Proline was successfully adsorbed on montmorillonite, haematite, olivine, and iron disulphide in anionic and zwitterionic chemical forms, being the predominant form directly related to the mineral structure and composition. Silicates (montmorillonite) dominate adsorption, whereas iron oxides (haematite) show the lowest molecular affinity. This approach will help to understand structure-affinity relationship between the mineral surfaces and proline, one of the nine amino acids generated in the Miller-Urey experiment.
矿物质在生命起源和益生元进化过程中的作用仍然未知且存在争议。矿物表面具有促进益生元聚合的潜力,因为它们能够吸附和浓缩生物分子,随后这些生物分子可以催化反应;然而,矿物主体与客体生物分子之间相互作用的确切性质仍有待了解。在此背景下,我们使用红外光谱、X射线光电子能谱(XPS)和X射线衍射(XRD)技术,通过评估L-脯氨酸与蒙脱石、橄榄石、二硫化铁和赤铁矿(具有益生元研究意义的矿物)在液体介质中的相互作用,对其进行了光谱表征。这项工作深入了解了脯氨酸(唯一的环状氨基酸)与这一系列矿物之间发生的化学过程,这些矿物各自具有特定的化学和晶体结构。脯氨酸以阴离子和两性离子化学形式成功吸附在蒙脱石、赤铁矿、橄榄石和二硫化铁上,其主要形式与矿物结构和组成直接相关。硅酸盐(蒙脱石)主导吸附,而氧化铁(赤铁矿)表现出最低的分子亲和力。这种方法将有助于理解矿物表面与脯氨酸之间的结构-亲和力关系,脯氨酸是米勒-尤里实验中产生的九种氨基酸之一。