维也纳大学Alexander Loy团队的一项最新研究发现微生物氧化铁呼吸耦合硫化物氧化。2025年8月27日出版的《自然》杂志发表了这项成果。

在此，该课题组研究人员对原核生物的硫代谢进行了全面的基因组分析，并揭示了能够氧化硫化物的细菌细胞外固相铁（iii）。基于涉及硫化合物异构转化的100多个基因的系统发育框架，该课题组人员记录了大多数细菌和古细菌门的硫循环能力。代谢重建预测在37个原核生物门的不同成员中硫化合物氧化和铁（iii）氧化物呼吸共同发生。生理和转录组学证据表明，一种培养的代表性嗜碱脱硫杆菌通过用铁氢化物作为细胞外铁（iii）电子受体将溶解的硫化物或单硫化铁（FeS）氧化为硫酸盐来自养生长。在与环境相关的硫化物浓度下，生物过程超过了非生物过程。这些发现扩大了已知的硫循环微生物的多样性，揭示了缺氧环境中硫和铁循环之间的生物机制，强调了微生物在全球元素循环中的基本作用。

研究人员表示，自生命出现以来，微生物一直在推动地球的硫循环，但微生物的硫循环能力及其与其他元素循环的整合尚不完全清楚。一种未被表征的代谢是硫化物氧化与铁（iii）氧化物还原的耦合，这是一个普遍存在的环境过程，迄今为止被认为是严格的非生物。

附：英文原文

Title: Microbial iron oxide respiration coupled to sulfide oxidation

Author: Chen, Song-Can, Li, Xiao-Min, Battisti, Nicola, Guan, Guoqing, Montoya, Maria A., Osvatic, Jay, Pjevac, Petra, Pollak, Shaul, Richter, Andreas, Schintlmeister, Arno, Wanek, Wolfgang, Mussmann, Marc, Loy, Alexander

Issue&Volume: 2025-08-27

Abstract: Microorganisms have driven Earth’s sulfur cycle since the emergence of life1,2,3,4,5,6, yet the sulfur-cycling capacities of microorganisms and their integration with other element cycles remain incompletely understood. One such uncharacterized metabolism is the coupling of sulfide oxidation with iron(iii) oxide reduction, a ubiquitous environmental process hitherto considered to be strictly abiotic7,8. Here we present a comprehensive genomic analysis of sulfur metabolism across prokaryotes, and reveal bacteria that are capable of oxidizing sulfide using extracellular solid phase iron(iii). Based on a phylogenetic framework of over hundred genes involved in dissimilatory transformation of sulfur compounds, we recorded sulfur-cycling capacity in most bacterial and archaeal phyla. Metabolic reconstructions predicted co-occurrence of sulfur compound oxidation and iron(iii) oxide respiration in diverse members of 37 prokaryotic phyla. Physiological and transcriptomic evidence demonstrated that a cultivated representative, Desulfurivibrio alkaliphilus, grows autotrophically by oxidizing dissolved sulfide or iron monosulfide (FeS) to sulfate with ferrihydrite as an extracellular iron(iii) electron acceptor. The biological process outpaced the abiotic process at environmentally relevant sulfide concentrations. These findings expand the known diversity of sulfur-cycling microorganisms and unveil a biological mechanism that links sulfur and iron cycling in anoxic environments, thus highlighting the fundamental role of microorganisms in global element cycles.

DOI: 10.1038/s41586-025-09467-0

Source: https://www.nature.com/articles/s41586-025-09467-0