Abiotic Synthesis of Substances Relative to the Origin of Life under the Oxidizing Atomosphere

氧化气氛下与生命起源相关的物质的非生物合成

• 批准号: 04453037
• 负责人: KIHARA Sorin
• 金额: $ 4.16万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04453037/
• 关键词: Oxidizing Atomosphere; Carbon Dioxide; Ammonia; Aqueous Solution; UV-irradiation; Nucleic Acid Bases; Amino Acids; Magnesium ion; 酸化的雰囲気; 炭酸ガス; 光合成; 合成条件; 共存塩

One of the objects of the investigation of "origin of life" is the estimation of the atomosphere of the primitive earth where living organisms were born. In the present work, it has been demonstrated that amino acids and nucleic acid bases can be synthesized from anaqueous solution containing both of CO_2 and NH_3 or ammonium carbonate by the irradiation of UV-light of wave length shorter than 280 nm at a temperature higher than 80ﾟC.This finding suggests that the abiotic synthesis of substances relative to the origin of life can be attained notonly under the reducing atomosphere composed of CH_4 and H_2 but also under the oxidizing atomosphere composed of CO_2 and O_2. Since the synthesis was found to be promoted remarkably by the addition of Mg^<2+> into the aqueous solution, the view can be drawn that the life was originated in the sea water, the aqueous salt solution. High concentrations of ammonuim oxalate and oxamic acid were found in the UV-irradiated solution, and hence these compounds were considered to be the possible intermediates in the photosynthesis. On the basis of the detailed investigation on the relation between the synthetic conditions and the yields of amino acids or nucleic acid bases and the effect of the coexistence of Mg^<2+> or the intermediates, the mechanism for the photosyntesis was elucidated as follows ; (1) The UV-irradiation of the aqueous ammonium carbonate solution produces ammonium oxalate. (2) Ammonium oxalate thus produced decomposes thermally resulting oxamic acid. Here, because of the strong complex formation between Mg^<2+> and oxamic acid, coexistence of Mg^<2+> promotes the thermal decomposition to oxamic acid and depresses the further decomposition of oxamic acid. (3) Oxamic acidproduces amino acids and nucleic acid bases absorbing UV-light of wave length shorter than 280 nm. (4) Relatives of saccharides might be synthesized from the intermediates such as oxalic

研究“生命起源”的目的之一是估计生物体诞生的原始地球的大气层。在本工作中，研究表明，在紫外光照射下，可以从CO_2和NH_3或碳酸铵的水溶液中合成氨基酸和核酸碱基。波长短于280 nm，温度高于80 ℃的光。这一发现表明，与生命起源有关的物质的非生物合成不仅可以在还原条件下实现，在由CH_4和H_2组成的氧化性气氛下，也可以在由CO_2和O_2组成的氧化性气氛下进行。由于发现在水溶液中加入Mg^<2+>能显著促进合成，因此可以得出这样的观点：生命起源于海水，即盐水溶液。在紫外光照射的溶液中发现了高浓度的草酸铵和草氨酸，因此这些化合物被认为是光合作用的可能中间产物。在详细研究了合成条件与氨基酸或核酸碱基产率的关系以及Mg^2+或中间体共存的影响的基础上，阐明了光合作用的机理：（1）碳酸铵水溶液经紫外光照射生成草酸铵。(2)由此产生的草酸铵热分解产生草氨酸。由于Mg^<2+>与草氨酸之间形成了强的络合物，Mg^<2+>的共存促进了草氨酸的热分解，并抑制了草氨酸的进一步分解。(3)草氨酸产生吸收波长小于280 nm的紫外光的氨基酸和核酸碱基。(4)草酸等中间体可合成出草酸的亲合物

项目成果

K.Ogura: "Ion Transfer at the Interface between Aqueous in the Presence of Concentrated Salts and Organic Studied by Polarography at the Electrolyte Solution Dropping Electrode." J.Electroanal.Chem.(1993)

K.Ogura：“通过极谱法在电解质溶液滴电极上研究浓盐存在下的水和有机物之间界面的离子转移。”

K.Ogura: "Ion Transfer at the Interface between an Aqueous Solution in the Presence of Concentrated Salts and an Organic Solution Studied by Polarography at the Electrolyte Solution Dropping Electrode" J.Electroanal.Chem.,. 352. 131-151 (1993)

K.Ogura：“通过极谱法在电解质溶液滴电极上研究浓盐存在下的水溶液与有机溶液之间界面的离子转移”J.Electroanal.Chem.,。

K.Ogura: "Ion Transfer at the Interface between an Aqueous Solution in the Presence of Concentrated Salts and an Organic Solution Studied by Polarography at the Electrolyte Solution Dropping Electrode" J.Electroanal.Chem.352. 131-151 (1993)

K.Ogura：“通过极谱法在电解质溶液滴电极上研究存在浓盐的水溶液和有机溶液之间界面上的离子转移”J.Electroanal.Chem.352。

S.Kihara et. al.: "Abiotic synthesis of substances relative to the origin of life under the oxidizing atomosphere." Transactions of The Research Institute of Oceanochemistry.7, (in press). (1994)

S.Kihara等。

K.Ogura et. al.: "Ion transfer at the interface between aqueous in the presence of concentrated salts and organic studied by polarography at the electrolyte solution dropping electrode." J.Electroanal.Chem.352. 131 (1993)

K.Ogura等。