Skolnick Jeffrey, Gao Mu
Georgia Institute of Technology, USA.
Biochem (Lond). 2021 Feb;43(1):4-12. doi: 10.1042/bio20210002. Epub 2021 Jan 20.
Many of life's molecules including proteins are built from chiral building blocks. What drove homochiral building block selection? Simulations on demi-chiral proteins containing equal numbers of d- and l-amino acids show that they possess many modern homochiral protein properties. They have the same global folds and could do the same biochemistry, with ancient, essential functions being most prevalent. They could synthesize chiral RNA and lipids which formed vesicles. RNA eventually combined with proteins creating ribosomes for more efficient protein synthesis, and thus, life began. Increased native state stability from homochiral secondary structure hydrogen bonding helped drive proteins towards homochirality.
包括蛋白质在内的许多生命分子都是由手性构件构建而成的。是什么驱动了同手性构件的选择呢?对含有等量d型和l型氨基酸的半手性蛋白质进行的模拟表明,它们具有许多现代同手性蛋白质的特性。它们具有相同的整体折叠结构,并且能够进行相同的生物化学过程,其中古老的基本功能最为普遍。它们能够合成手性RNA和脂质,这些物质形成了囊泡。RNA最终与蛋白质结合,形成核糖体以实现更高效的蛋白质合成,于是,生命开始了。同手性二级结构氢键导致的天然态稳定性增加,有助于推动蛋白质走向同手性。