Iron sulfide minerals crystallization in the presence of sulfur and clay minerals in media containing sulfate-reducing bacteria

This study aimed to synthesize Fe-sulfides in cultures of sulfate-reducing bacteria consortium under laboratory conditions with the time, Fe:S ratio, and addition or lack of oxidizing agent and/or clay mineral matrix. Here we sought to determine the role that SRM plays in iron sulfide mineral formation using a series of lab-based incubations that included live cultures and abiotic treatments. In the present contribution, the sulfate-reducing microorganisms were cultured with sulfur to investigate the effect of the oxidant agent on the nature of iron sulfides formed. In addition, the effect of the presence of a crystallization matrix, in the form of clay minerals, on the process of formation or morphology of crystallizing iron sulfides was investigated.These results allow an understanding of the evolution and mechanisms of pyrite formation in sulfate-reducing consortia cultures and discuss implications for natural environments.本研究旨在实验室条件下，通过调控培养时长、铁硫比、氧化剂添加与否以及黏土矿物基质的存在与否，在硫酸盐还原菌群落（sulfate-reducing bacteria consortium）的培养液中合成硫化铁矿物（Fe-sulfides）。本研究通过一系列包含活体培养组与非生物对照组的实验室培养实验，探究硫酸盐还原微生物（sulfate-reducing microorganisms, SRM）在硫化铁矿物形成过程中所发挥的作用。在本研究中，我们以硫为底物培养硫酸盐还原微生物，以考察氧化剂对所生成硫化铁矿物性质的影响；此外还探究了以黏土矿物形式存在的结晶基质，对硫化铁矿物的形成过程与结晶形貌的影响。本研究所得结果有助于理解硫酸盐还原菌群落培养液中黄铁矿（pyrite）的形成演化机制与过程，并探讨其对自然环境的启示意义。