Peptide-nucleotide microdroplets as a step towards a membrane-free protocell model
Peptide-nucleotide microdroplets as a step towards a membrane-free protocell model
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DOI：
10.1038/nchem.1110
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发表时间：
2011-09-01
期刊：
影响因子：
21.8
通讯作者：
Mann, Stephen
中科院分区：
文献类型：
--
作者：
Koga, Shogo;Williams, David S.;Mann, Stephen
虽然磷脂双分子层在现代细胞中普遍存在，但它们的不渗透性、缺乏动力学特性和合成复杂性难以与原代谢、生长和分裂的合理途径相协调。在这里，我们提出了一个替代的无膜模型，它表明，低分子量monocluttides和简单的阳离子肽自发地积累在水中成微滴是稳定的温度和盐浓度的变化，经历pH值诱导的周期的增长和衰减，并促进α-螺旋肽二级结构。此外，微滴选择性地螯合卟啉，无机纳米颗粒和酶，以分别产生捕光分子的超分子堆叠阵列，纳米颗粒介导的氧化酶活性和葡萄糖磷酸化的增强速率。综上所述，我们的研究结果表明，肽-核苷酸微滴可以被认为是一种新型的原始细胞模型，可用于开发新的生物反应器，原始的人工细胞和合理的途径，以在早期地球上出现基于脂质的区室化之前的益生元组织。
Although phospholipid bilayers are ubiquitous in modern cells, their impermeability, lack of dynamic properties, and synthetic complexity are difficult to reconcile with plausible pathways of proto-metabolism, growth and division. Here, we present an alternative membrane-free model, which demonstrates that low-molecular-weight mononucleotides and simple cationic peptides spontaneously accumulate in water into microdroplets that are stable to changes in temperature and salt concentration, undergo pH-induced cycles of growth and decay, and promote alpha-helical peptide secondary structure. Moreover, the microdroplets selectively sequester porphyrins, inorganic nanoparticles and enzymes to generate supramolecular stacked arrays of light-harvesting molecules, nanoparticle-mediated oxidase activity, and enhanced rates of glucose phosphorylation, respectively. Taken together, our results suggest that peptide-nucleotide microdroplets can be considered as a new type of protocell model that could be used to develop novel bioreactors, primitive artificial cells and plausible pathways to prebiotic organization before the emergence of lipid-based compartmentalization on the early Earth.