摘要
地球宜居性的演化与大气和海洋中氧气含量的变化密切相关,特别是大氧化事件(Great Oxidation Event,GOE)和新元古代氧化事件(Neoproterozoic Oxygenation Event,NOE)这两个关键的氧化事件。这些事件不仅影响地球的铁矿物形成过程,还对氮循环产生深远影响,如通过增加氧气浓度促进硝酸盐的生物可利用性。同样,卤素循环,包括卤化和脱卤过程,也可能受到早期地球氧化环境的影响。卤化酶,如卤过氧化物酶和卤化酶,需要氧气来氧化卤族元素并产生有机卤化物。因此,氧化事件可能在非生物产生卤化物以及卤化酶的增加和扩散中扮演了重要角色,从而促进地球上成千上万有机卤化物的生产。随着天然有机卤化物数量的增加,脱卤微生物的进化和脱卤基因(例如,还原脱卤酶基因)的水平转移速率可能加速。以脱卤球菌纲微生物为代表的专性脱卤微生物,包括Dehalococcoides和Dehalogenimonas菌株,被推断在寒武系时期出现。此类微生物在有机卤化物的生物地球化学循环中扮演着关键角色,然而关于它们的起源与进化及脱卤基因的演化信息仍然有限,限制了我们对地质时间尺度上卤素循环的理解。本研究旨在探讨地球宜居性演化过程中卤素的角色,特别是有机卤化物的起源和有机卤呼吸微生物的进化。我们将从地质时间尺度的角度,结合生物地球化学循环的视角,分析有机卤化物的生产、脱卤微生物的分布和演化,以及卤化酶和脱卤酶在地球氧化事件中的作用。通过这项研究,我们希望能够更深入地理解卤素循环在地球宜居性演化中的重要性,并为未来的环境管理和生物修复提供科学依据。
The evolution of Earth’s habitability is closely linked to changes in the atmospheric and oceanic oxygen levels,particularly the Great Oxidation Event(GOE)and the Neoproterozoic Oxygenation Event(NOE),two key oxidation events.These events not only affected Earth’s iron mineral processes but also had profound impacts on the nitrogen cycle,such as enhancing the bioavailability of nitrate through increased oxygen concentrations.Similarly,the halogen cycle,including halogenation and dehalogenation processes,may also have been influenced by the oxidative environment of early Earth.Halogenating enzymes,such as haloperoxidases and halogenases,require oxygen to oxidize halogen elements and generate organohalides.Therefore,oxidation events may have played a role in both the abiotic formation of organohalides(e.g.,through Fenton reactions and iron ions)and the increase and spread of halogenating enzymes,thus promoting the production of thousands of organohalides on Earth.With the rise in natural organohalides,the evolution of organohalide-respiring microorganisms and the horizontal gene transfer rates of dehalogenation genes(e.g.,reductive dehalogenase genes)may have accelerated.Obligate organohalide-respiring microorganisms Dehalococcoidia,such as Dehalococcoides and Dehalogenimonas strains,are inferred to have emerged during the Cambrian.These microorganisms play a crucial role in the biogeochemical cycling of organohalides.However,there is still limited information regarding their origin and evolution,as well as the evolution of dehalogenation genes,which hinders our understanding of the halogen cycle on geological time scales.This study aims to explore the role of halogens in the evolution of Earth’s habitability,particularly the origin of organohalides and the evolution of organohalide-respiring microorganisms.By approaching this topic from a geological time scale and integrating the perspective of biogeochemical cycles,we will analyze the production of organohalides,the distribution and evolution of organohalide-respiring microorganisms,and the role of halogenating enzymes and dehalogenases during Earth’s oxidation events.Through this research,we hope to gain a deeper understanding of the significance of the halogen cycle in the evolution of Earth’s habitability and provide scientific evidence for future environmental management and bioremediation.
作者
杨毅
钟音
汪善全
王红岩
廖恒毅
王欣
YANG Yi;ZHONG Yin;WANG Shanquan;WANG Hongyan;LIAO Hengyi;WANG Xin(Key Laboratory of Pollution Ecology and Environmental Engineering,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China;Key Laboratory of Forest Ecology and Silviculture,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China;Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China;Sun Yat-Sen University,Guangzhou 510006,China;University of Chinese Academy of Sciences,Beijing 100049,China;University of Hawaii at Manoa,Honolulu,Hawaii 96822,United States)
出处
《地学前缘》
北大核心
2025年第3期156-167,共12页
Earth Science Frontiers
基金
国家重点研发计划项目(2023YFE0122000)
国家自然科学基金项目(42177220)。
关键词
卤素循环
地球宜居性演化
脱卤微生物
有机卤呼吸
还原脱卤酶
halogen cycle
evolution of Earth’s habitability
organohalide-respiring microorganisms
organohalide respiration
reductive dehalogenase
