Microbial diversity and biomineralization in low-temperature hydrothermal iron-silica-rich precipitates of the Lau Basin hydrothermal field
Microbial diversity and biomineralization in low-temperature hydrothermal iron-silica-rich precipitates of the Lau Basin hydrothermal field
复制标题
Lau盆地热液田低温热液富铁硅沉积物中的微生物多样性和生物矿化
DOI：
10.1111/j.1574-6941.2012.01367.x
复制
发表时间：
2012-07-01
影响因子：
4.2
通讯作者：
Fang, Jiasong
中科院分区：
文献类型：
--
作者：
Li, Jiangtao;Zhou, Huaiyang;Fang, Jiasong
从位于东劳伸展中心的CDE热液场收集了富铁硅的低温热液沉淀。系统发育分析表明，沉积物以a-变形菌门和海洋I群古细菌为主。超微结构分析提示富硅铁矿床的细菌成因。检测到的独特生物特征包括直丝、螺旋茎和弯曲不规则丝，其外观结构与已知的铁氧化属细螺旋体（Leptothrix spp.）、Gallionella spp.和Mariprofundus spp.的排泄结构相似。16S rRNA基因分析证实了中性嗜铁氧化细菌的存在，并检测到与Gallionella spp.和提出的？变形菌门课。矿物学和整体地球化学分析表明，沉淀主要以无定形二氧化硅为主，铁含量低。基于微生物学、地球化学和矿物学分析，我们认为在CDE热液区硅化是一个普遍的过程，微生物细胞和相关超微结构可能是二氧化硅沉淀的成核模板。
Ironsilica-rich low-temperature hydrothermal precipitates were collected from the CDE hydrothermal field located at the East Lau Spreading Center. Phylogenetic analysis showed that the precipitates were dominated by the members of a-proteobacteria and marine group I archaea. Ultrastructural analysis suggested the bacteriogenic origin of the ironsilica-rich deposits. Distinctive biosignatures detected included straight filaments, helical stalks and curved irregular filaments, which were similar in appearance to those structures excreted by the known iron-oxidizing genera Leptothrix spp., Gallionella spp. and Mariprofundus spp. 16S rRNA gene analysis confirmed the presence of neutrophilic iron-oxidizing bacteria with the detection of phylotypes clustering with Gallionella spp. and the proposed ?-proteobacteria class. Mineralogy and bulk geochemical analyses showed that the precipitates were dominated by amorphous silica with low amounts of iron. Based on microbiological, geochemical and mineralogical analyses, we conclude that silicification was a common process and microbial cells and related ultrastructures likely acted as nucleation templates for silica precipitation in the CDE hydrothermal field.