Matthew J. Roche, M. Fox‐Powell, R. Hamp, J. Byrne
{"title":"铁还原是土卫二海洋中可行的代谢途径","authors":"Matthew J. Roche, M. Fox‐Powell, R. Hamp, J. Byrne","doi":"10.1017/s1473550423000125","DOIUrl":null,"url":null,"abstract":"\n Recent studies postulated the viability of a suite of metabolic pathways in Enceladus’ ocean motivated by the detection of H2 and CO2 in the plumes – evidence for available free energy for methanogenesis driven by hydrothermal activity at the moon's seafloor. However, these have not yet been explored in detail. Here, a range of experiments were performed to investigate whether microbial iron reduction could be a viable metabolic pathway in the ocean by iron-reducing bacteria such as Geobacter sulfurreducens. This study has three main outcomes: (i) the successful reduction of a number of crystalline Fe(III)-bearing minerals predicted to be present at Enceladus was shown to take place to differing extents using acetate as an electron donor; (ii) substantial bacterial growth in a simulated Enceladus ocean medium was demonstrated using acetate and H2(g) separately as electron donors; (iii) microbial iron reduction of ferrihydrite was shown to partially occur at pH 9, the currently accepted value for Enceladus’ ocean, whilst being severely hindered at the ambient ocean temperature of 0°. This study proposes the possibilities for biogeochemical iron cycling in Enceladus’ ocean, suggesting that a strain of iron-reducing bacteria can effectively function under Enceladus-like conditions.","PeriodicalId":13879,"journal":{"name":"International Journal of Astrobiology","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Iron reduction as a viable metabolic pathway in Enceladus’ ocean\",\"authors\":\"Matthew J. Roche, M. Fox‐Powell, R. Hamp, J. Byrne\",\"doi\":\"10.1017/s1473550423000125\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"\\n Recent studies postulated the viability of a suite of metabolic pathways in Enceladus’ ocean motivated by the detection of H2 and CO2 in the plumes – evidence for available free energy for methanogenesis driven by hydrothermal activity at the moon's seafloor. However, these have not yet been explored in detail. Here, a range of experiments were performed to investigate whether microbial iron reduction could be a viable metabolic pathway in the ocean by iron-reducing bacteria such as Geobacter sulfurreducens. This study has three main outcomes: (i) the successful reduction of a number of crystalline Fe(III)-bearing minerals predicted to be present at Enceladus was shown to take place to differing extents using acetate as an electron donor; (ii) substantial bacterial growth in a simulated Enceladus ocean medium was demonstrated using acetate and H2(g) separately as electron donors; (iii) microbial iron reduction of ferrihydrite was shown to partially occur at pH 9, the currently accepted value for Enceladus’ ocean, whilst being severely hindered at the ambient ocean temperature of 0°. This study proposes the possibilities for biogeochemical iron cycling in Enceladus’ ocean, suggesting that a strain of iron-reducing bacteria can effectively function under Enceladus-like conditions.\",\"PeriodicalId\":13879,\"journal\":{\"name\":\"International Journal of Astrobiology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.7000,\"publicationDate\":\"2023-07-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Astrobiology\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.1017/s1473550423000125\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Astrobiology","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1017/s1473550423000125","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
Iron reduction as a viable metabolic pathway in Enceladus’ ocean
Recent studies postulated the viability of a suite of metabolic pathways in Enceladus’ ocean motivated by the detection of H2 and CO2 in the plumes – evidence for available free energy for methanogenesis driven by hydrothermal activity at the moon's seafloor. However, these have not yet been explored in detail. Here, a range of experiments were performed to investigate whether microbial iron reduction could be a viable metabolic pathway in the ocean by iron-reducing bacteria such as Geobacter sulfurreducens. This study has three main outcomes: (i) the successful reduction of a number of crystalline Fe(III)-bearing minerals predicted to be present at Enceladus was shown to take place to differing extents using acetate as an electron donor; (ii) substantial bacterial growth in a simulated Enceladus ocean medium was demonstrated using acetate and H2(g) separately as electron donors; (iii) microbial iron reduction of ferrihydrite was shown to partially occur at pH 9, the currently accepted value for Enceladus’ ocean, whilst being severely hindered at the ambient ocean temperature of 0°. This study proposes the possibilities for biogeochemical iron cycling in Enceladus’ ocean, suggesting that a strain of iron-reducing bacteria can effectively function under Enceladus-like conditions.
期刊介绍:
International Journal of Astrobiology is the peer-reviewed forum for practitioners in this exciting interdisciplinary field. Coverage includes cosmic prebiotic chemistry, planetary evolution, the search for planetary systems and habitable zones, extremophile biology and experimental simulation of extraterrestrial environments, Mars as an abode of life, life detection in our solar system and beyond, the search for extraterrestrial intelligence, the history of the science of astrobiology, as well as societal and educational aspects of astrobiology. Occasionally an issue of the journal is devoted to the keynote plenary research papers from an international meeting. A notable feature of the journal is the global distribution of its authors.