Feldspars are a group of tectosilicate minerals terminated with a full layer of hydroxyl groups and have been regarded as “hotbed” for birth of life. In this study, periodic density functional theory calculations are conducted to address two associated issues, as adsorption of amino acids and conformational interconversions over feldspar surfaces. Distribution of glycine isomers depends strongly on the number of interacted surface silanols (n), and canonical isomers exist exclusively for n ≤ 2 while zwitterions predominate for n = 3. Adsorption of amino acids is significantly affected by sidechains, especially those forming H‐bonds with surfaces; however, sidechain contacts with feldspar surfaces disfavor zwitterion stabilization, and zwitterions become preferred without sidechain contacts. For all amino acids, conformational interconversions undergo four elementary steps, and proton transfer between two carboxylic‐O atoms (step 2) is always rate‐decisive. Step 2 is greatly accelerated with catalysis of surface silanols and activation barriers depend significantly on sidechains. All amino acids have moderate activation barriers and conformational interconversions (in both forward and reverse directions) proceed favorably at ambient conditions. Sidechains of amino acids exhibit influences through sidechain contacts with surfaces rather than as substituent effect.

中文翻译：

---

走向长石表面的生命起源：氨基酸的吸附和构象互变的催化

长石是一组具有完整的羟基基团的硅酸盐矿物，被认为是生命诞生的“温床”。在这项研究中，进行周期性密度泛函理论计算以解决两个相关问题，如氨基酸的吸附和长石表面的构象互变。甘氨酸异构体的分布在很大程度上取决于相互作用的表面硅烷醇（n）的数量，并且典型的异构体仅存在于n≤2，而两性离子占主导的n =3。氨基酸的吸附受侧链的影响很大，尤其是那些形成H键的氨基酸有表面 然而，长石表面的侧链接触不利于两性离子的稳定，两性离子在没有侧链接触的情况下成为优选的。对于所有氨基酸，构象互变经历四个基本步骤，并且两个羧基-O原子之间的质子转移（步骤2）始终是决定性的。表面硅烷醇的催化极大地加快了步骤2的活化，活化壁垒很大程度上取决于侧链。所有氨基酸均具有适度的激活屏障，并且构象互变（正向和反向）在环境条件下均能顺利进行。氨基酸的侧链通过与表面的侧链接触而不是取代效应而显示影响。所有氨基酸均具有适度的激活屏障，并且构象互变（正向和反向）在环境条件下均能顺利进行。氨基酸的侧链通过与表面的侧链接触而不是取代效应而显示影响。所有氨基酸均具有适度的激活屏障，并且构象互变（正向和反向）在环境条件下均能顺利进行。氨基酸的侧链通过与表面的侧链接触而不是取代效应而显示影响。