由酸和的可用性驱动的原始的同体性聚形成
Chen Chen1, Ruiqin Yi2, Motoko Igisu3
1Earth-Life Science Institute, Institute of Future Science, Institute of Science Tokyo, Meguro-ku, Tokyo 152-8550, Japan.
概括
离子 (Ca2+) 影响了酸聚合,这是生命起源的一个关键步骤. 这种离子介导的过程可能选择了性单体,从而产生了早期生命中必不可少的同性聚合物.
科学领域:
- 天体生物学与生命起源研究研究
- 益生菌化学和分子进化研究
背景情况:
- 阿尔法-氧酸 (αHAs) 是生命早期可信的益生菌单体.
- αHAs的脱水聚合形成聚合物,对原细胞发育至关重要.
- 同人性是一种生命的基本性质,但它的前生物起源是有争议的.
研究的目的:
- 研究 homochiral 聚合物合成的酸 (TA) 聚合机制.
- 探索离子 (Ca2+) 在TA聚合和反体选择中的作用.
- 阐明了在益生菌系统中同化性出现的途径.
主要方法:
- 研究了酸 (d-TA,l-TA) 和白血酸 (dl-TA) 的脱水聚合.
- 通过结晶研究了Ca2+离子对TA单体可用性的影响.
- 分析了不同TA立体异构体的聚合动态的Ca2+调制.
主要成果:
- 乙纯TA高效聚合,而种族性TA聚合被抑制.
- 2+离子选择性地结晶了血TA,丰富了剩余的溶液的反体过剩.
- Ca2+ 抑制了 enantiopure TA 聚合,但使得 raceme dl-TA 聚合成为可能.
结论:
- 2+离子可能间接选择了性单体,并促进了同性.
- 不同的离子可用性可能推动了同体性聚合物的出现.
- 这提供了从无生命物质到地球上早期生命的潜在途径.
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