11:30 〜 11:45
[BBG02-09] Microbial Growth Characterisation on Iron and Carbonaceous Meteorites Under Laboratory and Primitive Earth Conditions
Recently, studies of the space sciences have been greatly impacted by ongoing research on meteorite-microorganism interaction. The biological potential of meteorites has been revealed in past studies, and it has been elicited that they provide nutrients and energy sources to microorganisms in diverse ways. In terms of microbial life, meteorites, especially meteoritic minerals, provide a range of benefits, including protection, nutrients, and energy [1]. Various studies have revealed that certain microorganisms can be cultured within iron and carbonaceous meteorites. Such examples contain the growth of Leptospirillum ferrooxidans and Acidithiobacillus ferrooxidans on the Toluca meteorite [2], Acidithiobacillus ferrooxidans on Casas Grandes and Cape York meteorite [3], thermoacidophile archaea Metallosphaera sedula on NWA 1172 meteorite [4]. Moreover, it has been shown that carbonaceous chondrites can act as an exogenous source of nutrients and energy and are able to promote bacterial growth [5]. Understanding microbial survival in meteorites will help shed light on how life can be sustained in inhospitable and/or extreme environments, as well as how microbes can process exogenous resources and thus how microorganisms can be used in space missions. Further knowledge on the biosignatures left behind from microbe-meteorite interactions allows researchers to predict how life was formed and developed during the early Earth.
In this study, we aimed to clarify microbes originated meteorite samples by cultivation without external sources of inoculum. The second aim is to testify the growth of thermophilic microbes under conditions analogous to the early Earth environment. For the latter aim, microbial populations from a terrestrial hot spring are inoculated to liquid medium including meteorite samples as carbon and/or energy sources.
For the cultivation, freshwater medium contained powdered meteorite samples or their blocks with variable electron acceptors such as SO4, NO3, CO2, elemental S, Fe (III) and O2. Meteorite samples of Agoudal (iron IIAB) and NWA 5508 (carbonaceous CV3) were selected for incubation. As the media was incubated at 30 degree celusius without inoculum, microbial growth could be originated from the meteorite samples. For 60-degree-celusius incubation, microbial population from the terrestrial hot spring called Jinata Onsen on Shikinejima Island will be inoculated.
In this presentation, we will present results from cultivation in terms of cell number and 16S rRNA gene sequences and from solid characterizations of microbe-mineral-organic assemblages by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR).
References
1. Dong, H. et al. A critical review of mineral-microbe interaction and co-evolution: mechanisms and applications. Natl Sci Rev. 9, (2022).
2. Gonzales-Toril, E. et al. Iron meteorites can support the growth of acidophilic chemolithoautotrophic microorganisms. Astrobiology. 5, 406-414 (2005).
3. Gronstal, A. et al. Laboratory experiments on the weathering of iron meteorites and carbonaceous chondrites by iron-oxidizing bacteria. Meteorit Planet Sci. 44, 233-247 (2009).
4. Milojevic, T. et al. Cultivation With Powdered Meteorite (NWA 1172) as the Substrate Enhances Low-Temperature Preservation of the Extreme Thermoacidophile Metallosphaera sedula. Frontiers in Astronomy and Space Sciences. 7, 553459 (2020).
5. Waajen, A.C. et al. Life on Earth can grow on extraterrestrial organic carbon. Scientific Reports 2024 14, 1-9 (2024).
In this study, we aimed to clarify microbes originated meteorite samples by cultivation without external sources of inoculum. The second aim is to testify the growth of thermophilic microbes under conditions analogous to the early Earth environment. For the latter aim, microbial populations from a terrestrial hot spring are inoculated to liquid medium including meteorite samples as carbon and/or energy sources.
For the cultivation, freshwater medium contained powdered meteorite samples or their blocks with variable electron acceptors such as SO4, NO3, CO2, elemental S, Fe (III) and O2. Meteorite samples of Agoudal (iron IIAB) and NWA 5508 (carbonaceous CV3) were selected for incubation. As the media was incubated at 30 degree celusius without inoculum, microbial growth could be originated from the meteorite samples. For 60-degree-celusius incubation, microbial population from the terrestrial hot spring called Jinata Onsen on Shikinejima Island will be inoculated.
In this presentation, we will present results from cultivation in terms of cell number and 16S rRNA gene sequences and from solid characterizations of microbe-mineral-organic assemblages by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR).
References
1. Dong, H. et al. A critical review of mineral-microbe interaction and co-evolution: mechanisms and applications. Natl Sci Rev. 9, (2022).
2. Gonzales-Toril, E. et al. Iron meteorites can support the growth of acidophilic chemolithoautotrophic microorganisms. Astrobiology. 5, 406-414 (2005).
3. Gronstal, A. et al. Laboratory experiments on the weathering of iron meteorites and carbonaceous chondrites by iron-oxidizing bacteria. Meteorit Planet Sci. 44, 233-247 (2009).
4. Milojevic, T. et al. Cultivation With Powdered Meteorite (NWA 1172) as the Substrate Enhances Low-Temperature Preservation of the Extreme Thermoacidophile Metallosphaera sedula. Frontiers in Astronomy and Space Sciences. 7, 553459 (2020).
5. Waajen, A.C. et al. Life on Earth can grow on extraterrestrial organic carbon. Scientific Reports 2024 14, 1-9 (2024).