Clay minerals associated with microbial body and trace fossils in rocks deposited in shallow marine environments have importance in understanding microbial preservation. We show experimentally that the presence of suspended detrital clays in oceanic environments is a crucial control on the formation of co-aggregates between filamentous cyanobacteria and clay minerals and is thus important in the sedimentation and subsequent preservation of cyanobacteria. Strong cyanobacteria-clay co-aggregation occurs over short time periods (3–7 days) in the presence of 10 mg/L of suspended clay minerals (illite, kaolinite and montmorillonite), and the occurrence of co-aggregation is not affected by the type of clay minerals present. The cyanobacteria-clay co-aggregation shows a pronounced effect on preserving the biomass of cyanobacteria. The surface properties of clay minerals and cyanobacteria, specifically the electrostatic attraction between the oppositely charged surfaces of cyanobacteria and clay minerals, are the main drivers of cyanobacteria-clay co-aggregation. Chemical effects, such as the deprotonation of COOH groups in active organic compounds secreted by cyanobacteria and therefore the release of H⁺, result in local dissolution of clay and slight structure changes in the bulk of clay minerals. Compared with the suspended clay, dissolved ions (Si, Al or Fe ions) are of secondary importance in the formation of cyanobacteria-clay co-aggregates, although these ions further promote this process. Overall, the cyanobacteria-clay co-aggregation not only substantially affects the preservation of cyanobacteria, but also may have potentially important and profound impacts on related geochemical processes such as microbial dissolution of clay minerals and the biogeochemical Si cycle in marine environments.

与微生物体有关的粘土矿物和沉积在浅海环境中的岩石中的微量化石对理解微生物的保存很重要。我们通过实验表明，海洋环境中悬浮的碎屑黏土的存在是对丝状蓝细菌和黏土矿物之间共聚集体形成的关键控制，因此在蓝细菌的沉积和后续保存中很重要。在10 mg / L悬浮粘土矿物（伊利石，高岭石和蒙脱土）存在下，短时间内（3-7天）会发生强蓝藻-粘土共聚集，并且共聚集的发生不受硅藻土的影响。存在的粘土矿物的类型。蓝藻-粘土共聚集对保留蓝藻的生物量显示出显着效果。粘土矿物和蓝细菌的表面特性，特别是蓝细菌和粘土矿物带相反电荷的表面之间的静电吸引，是蓝细菌-粘土共聚集的主要驱动力。化学作用，例如去质子化蓝细菌分泌的活性有机化合物中的COOH基团以及因此释放的H ⁺导致粘土的局部溶解和大部分粘土矿物的轻微结构变化。与悬浮粘土相比，溶解离子（Si，Al或Fe离子）在蓝藻-粘土共聚集体的形成中具有次要的重要性，尽管这些离子进一步促进了该过程。总体而言，蓝藻-粘土共聚集不仅会严重影响蓝藻的保存，而且可能会对相关的地球化学过程（如粘土矿物的微生物溶解和海洋环境中的生物地球化学Si循环）产生重要而深远的影响。