Prebiotic synthesis of cysteine peptides that catalyze peptide ligation in neutral water

doi:10.1126/science.abd5680

GSTDTAP > 气候变化

DOI	10.1126/science.abd5680
	Prebiotic synthesis of cysteine peptides that catalyze peptide ligation in neutral water
	Callum S. Foden; Saidul Islam; Christian Fernández-García; Leonardo Maugeri; Tom D. Sheppard; Matthew W. Powner
	2020-11-13
发表期刊	Science
出版年	2020
英文摘要	Among amino acids, cysteine is highly reactive as a nucleophile, metal ligand, and participant in redox and radical reactions. These properties make cysteine attractive as a component of prebiotic chemistry, but traditional Strecker synthesis of α-aminonitriles, which can serve as peptide precursors, cannot produce free cysteine. Foden et al. found that a simple acylation of the free amine prevented degradation of cysteine nitrile and enabled synthesis of this cysteine precursor from acetyl dehydroalanine nitrile and a sulfide donor (see the Perspective by Muchowska and Moran). When combined with other proteinogenic α-aminonitriles, acetylcysteine or derivative thiols catalyzed efficient peptide ligation in water. These results highlight how prebiotic synthesis of precursors can also generate function by creating a catalyst for polymerization. Science , this issue p. [865][1]; see also p. [767][2] Peptide biosynthesis is performed by ribosomes and several other classes of enzymes, but a simple chemical synthesis may have created the first peptides at the origins of life. α-Aminonitriles—prebiotic α–amino acid precursors—are generally produced by Strecker reactions. However, cysteine’s aminothiol is incompatible with nitriles. Consequently, cysteine nitrile is not stable, and cysteine has been proposed to be a product of evolution, not prebiotic chemistry. We now report a high-yielding, prebiotic synthesis of cysteine peptides. Our biomimetic pathway converts serine to cysteine by nitrile-activated dehydroalanine synthesis. We also demonstrate that N -acylcysteines catalyze peptide ligation, directly coupling kinetically stable—but energy-rich—α-amidonitriles to proteinogenic amines. This rare example of selective and efficient organocatalysis in water implicates cysteine as both catalyst and precursor in prebiotic peptide synthesis. [1]: /lookup/doi/10.1126/science.abd5680 [2]: /lookup/doi/10.1126/science.abf1698
领域	气候变化 ; 资源环境
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引用统计
文献类型	期刊论文
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/304156
专题	气候变化资源环境科学
推荐引用方式 GB/T 7714	Callum S. Foden,Saidul Islam,Christian Fernández-García,et al. Prebiotic synthesis of cysteine peptides that catalyze peptide ligation in neutral water[J]. Science,2020.
APA	Callum S. Foden,Saidul Islam,Christian Fernández-García,Leonardo Maugeri,Tom D. Sheppard,&Matthew W. Powner.(2020).Prebiotic synthesis of cysteine peptides that catalyze peptide ligation in neutral water.Science.
MLA	Callum S. Foden,et al."Prebiotic synthesis of cysteine peptides that catalyze peptide ligation in neutral water".Science (2020).