著者

北台 紀夫 青野 真士 大野 克嗣

出版者

一般社団法人日本地球化学会

雑誌

地球化学 (ISSN:03864073)

巻号頁・発行日

vol.50, no.3, pp.155-176, 2016-09-25 (Released:2016-09-25)

参考文献数

156

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The origin of life must be studied through addressing a problem of the emergence of a free-energetically open complex system, rather than a problem of abiotic syntheses of various building blocks of life (Aono et al., 2015). One of the key aspects of the origin question is the origin of metabolism, since no (genetic) information may be preserved without ample and ordered materials supply. Thus, from the perspective of the origin of ‘proto-metabolism' we critically review currently prevailing approaches to the origin problem. Then, referring to the latest biological and geochemical findings, we will describe a scenario of the electrochemically driven emergence of ‘proto-metabolism' together with experimental proposals.

著者

北台 紀夫

出版者

一般社団法人日本地球化学会

雑誌

地球化学 (ISSN:03864073)

巻号頁・発行日

vol.53, no.3, pp.91-105, 2019-09-25 (Released:2019-09-25)

参考文献数

116

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How and where did life on Earth originate? Did the life’s origin happen from a combination of a huge number of geological events that were specially and temporally separated from each other, or did it occur within a local environment through a series of chemical processes that were compatible with the conditions prevailing within the setting? One of the key sites to resolve these questions is deep-sea hydrothermal systems, where the emergence of protometabolism through sulfides-promoted abiotic CO2 fixation has long been suggested to be the most plausible initial process toward the origin of life. However, geochemical mechanisms to harness the reductive power provided by hydrothermal systems remain to be elucidated. Here, this review introduces “geoelectrochemistry” as a general potent means to realize protometabolism at the vent–seawater interface in early ocean hydrothermal systems. Based on the relevant field, laboratory, and theoretical investigations of these systems, together with the latest astronomical observations of extraterrestrial planets/satellites, the fundamental nature of driver for life are discussed as a base to consider the ubiquity and similarity of life in Universe.