Abstract

In this work, we investigate the long-term (>30 days) competitive interaction of viable Gram-negative bacterium Shewanella putrefaciens and dissolved fulvic acids for aqueous cations of Mn(II) whose compounds play crucial role in geochemistry and mineralogy. It has been proved that the previously discovered bio-precipitates (Mn phosphate and Mn carbonate) were also formed in the presence of environmentally relevant concentrations of fulvic acids by the lower density bacterial cells during long-term sorption of dissolved Mn(II) under the same experimental conditions. However, fulvic acids altered the ratio between the above two compounds and caused the formation of an additional mineral, Mn hydrous oxides. The later finding put in order the entire mineralogical information about Mn-containing minerals dominated by Mn hydrous oxides; as a matter of fact, natural waters/soils always contain humic substances which affect biomineralization processes. The experiments with very high concentrations of fulvic acids showed that at equal binding powers of bacterial cells and aqueous fulvic acids, the latter completely depressed Mn(II) sorption by S. putrefaciens. This basic science study, however, for the first time demonstrated that the beginning of bio-precipitation processes is associated with an intermediate metabolic bacterial state in which the unicells are still viable but nonculturable anymore.

抽象的

在这项工作中，我们调查了存活的革兰氏阴性细菌恶臭希瓦氏菌（Shewanella putrefaciens）的长期（> 30天）竞争性相互作用。以及溶解的富里酸用于Mn（II）的水性阳离子，其化合物在地球化学和矿物学中起着至关重要的作用。业已证明，先前发现的生物沉淀物（磷酸锰和碳酸锰）也是在环境相关浓度的富里酸存在的情况下，在较低浓度的细菌细胞长期吸附溶解的Mn（II）的情况下，由较低密度的细菌细胞形成的。相同的实验条件。然而，黄腐酸改变了上述两种化合物之间的比例，并导致形成另外的矿物质Mn水合氧化物。后来的发现整理了有关以锰水合氧化物为主的含锰矿物的完整矿物学信息。实际上，天然水/土壤总是含有腐殖质，会影响生物矿化过程。腐烂链球菌。但是，这项基础科学研究首次证明了生物沉淀过程的开始与中间代谢细菌状态有关，在这种状态下，单细胞仍然可以存活，但无法再培养。