Primitive Photosynthetic Architectures Based on Self‐Organization and Chemical Evolution of Amino Acids and Metal Ions

• Published in: Advanced science 2018-06, Vol.5 (6), p.1701001-n/a
• Main Authors: Liu, Kai, Ren, Xiaokang, Sun, Jianxuan, Zou, Qianli, Yan, Xuehai
• Format: Article
• Language: English
• Subjects: Amino acids; Carbon dioxide; chemical evolution; Chromatography; Decomposition; Energy; Evolution; Heat; High temperature; Light; Microscopy; Nanocrystals; Photocatalysis; Photosynthesis; photosynthetic architectures; Prebiotics; primitive pigments; Scanning electron microscopy; self‐organization; Spectrum analysis
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.201701001

The emergence of light‐energy‐utilizing metabolism is likely to be a critical milestone in prebiotic chemistry and the origin of life. However, how the primitive pigment is spontaneously generated still remains unknown. Herein, a primitive pigment model based on adaptive self‐organization of amino acids (Cystine, Cys) and metal ions (zinc ion, Zn2+) followed by chemical evolution under hydrothermal conditions is developed. The resulting hybrid microspheres are composed of radially aligned cystine/zinc (Cys/Zn) assembly decorated with carbonate‐doped zinc sulfide (C‐ZnS) nanocrystals. The part of C‐ZnS can work as a light‐harvesting antenna to capture ultraviolet and visible light, and use it in various photochemical reactions, including hydrogen (H2) evolution, carbon dioxide (CO2) photoreduction, and reduction of nicotinamide adenine dinucleotide (NAD+) to nicotinamide adenine dinucleotide hydride (NADH). Additionally, guest molecules (e.g., glutamate dehydrogenase, GDH) can be encapsulated within the hierarchical Cys/Zn framework, which facilitates sustainable photoenzymatic synthesis of glutamate. This study helps deepen insight into the emergent functionality (conversion of light energy) and complexity (hierarchical architecture) from interaction and reaction of prebiotic molecules. The primitive pigment model is also promising to work as an artificial photosynthetic microreactor. A primitive photosynthetic architecture model is developed using chemical evolution of cystines and zinc ions in the form of adaptive self‐organization with the assistance of heat energy. The obtained hybrid microspheres integrate in situ mineralized carbonate‐doped zinc sulfide and hierarchical cystine/zinc frameworks, which can capture sunlight for primitive photosynthesis and encapsulate enzymes to work as photoenzymatic microreactor.