Protoenzymes: The Case of Hyperbranched Polymer-Scaffolded ZnS Nanocrystals
Protoenzymes: The Case of Hyperbranched Polymer-Scaffolded ZnS Nanocrystals
复制标题
DOI：
10.3390/life10080150
复制
发表时间：
2020-03
期刊：
影响因子：
--
通讯作者：
Irena Mamajanov;Melina Caudan;Tony Z. Jia
中科院分区：
文献类型：
--
作者：
Irena Mamajanov;Melina Caudan;Tony Z. Jia
酶是一种生物催化剂，由生物聚合物支架增强的小分子、金属或团簇催化剂组成。可以想象，在化学进化的早期，祖先酶选择了更简单、更容易组装的支架。在这里，我们描述了这种可能的原酶：超支化聚合物-支架金属-硫化物纳米晶体。用简单的方法制备了超支化聚乙烯亚胺（HyPEI）和柠檬酸甘油聚合物负载的ZnS纳米晶体（NCs）。透射电子显微镜（TEM）分析的hypei支持的nc显示球形颗粒平均大小为10纳米，在14天的孵育过程中只经历适度的聚集。聚合物负载的ZnS NCs在伊红B光降解实验中显示出较高的光催化活性，使其成为研究由光催化原代谢氧化还原反应网络主导的“Zn世界”理论下生命起源的一个有吸引力的模型。然而，这种催化剂可以很容易地适应于广泛应用于不同的原酶体系。
Enzymes are biological catalysts that are comprised of small-molecule, metal, or cluster catalysts augmented by biopolymeric scaffolds. It is conceivable that early in chemical evolution, ancestral enzymes opted for simpler, easier to assemble scaffolds. Herein, we describe such possible protoenzymes: hyperbranched polymer-scaffolded metal-sulfide nanocrystals. Hyperbranched polyethyleneimine (HyPEI) and glycerol citrate polymer-supported ZnS nanocrystals (NCs) are formed in a simple process. Transmission electron microscopy (TEM) analyses of HyPEI-supported NCs reveal spherical particles with an average size of 10 nm that undergo only a modest aggregation over a 14-day incubation. The polymer-supported ZnS NCs are shown to possess a high photocatalytic activity in an eosin B photodegradation assay, making them an attractive model for the study of the origin of life under the “Zn world” theory dominated by a photocatalytic proto-metabolic redox reaction network. The catalyst, however, could be easily adapted to apply broadly to different protoenzymatic systems.