Theoretical understanding of the population dynamics and evolution of chemotrophs under the limitation of metabolic energy acquisition per redox reaction.

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06853
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 45040:Ecology and environment-related
• Research Institution: Nara Women's University
• Principal Investigator: Seto Mayumi 奈良女子大学, 自然科学系, 助教 (10512717)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 微生物生態 / 非平衡熱力学 / 数理モデリング / 生物エネルギー論 / 酸化還元反応 / 化学合成微生物 / 個体群動態 / ギブスエネルギー

Outline of Final Research Achievements

The fundamental ecological theories have been developed based on observations of the Earth's surface ecosystems (e.g., terrestrial and coastal ecosystems). meanwhile, the deep subsurface environments also harbor enormous biomass, in which bacteria and archaea support primary production. The amount of energy available in the deep sea is far less than that available in surface ecosystems. In this study, we conducted a theoretical study using a population dynamics model to understand microbial communities and ecosystems that are independent of light as an energy source. The results revealed that microorganisms increase not only the reaction rate but also the energy conversion efficiency by passing metabolites to other microorganisms.

Free Research Field

数理生物学

Academic Significance and Societal Importance of the Research Achievements

地下生態系に存在する細菌や古細菌の多くは電子移動を伴う化学反応を利用して自らのエネルギーに転換し、生物生産を支える。こうしたエネルギー利用形態の生物は地球の最古の生命に近い形態であることが示唆されている。よって、光に依存しない微生物生態系を理解することは、初期生命が生態系を築くに至るプロセスを知るために役に立つ。また、生態学のこれまでの基盤理論に地下生態系の理論を追加し、比較することで、より普遍的な生態系理論の確立を目指すことができる。