Biomineralization of phototrophic microbes in silica-enriched hot springs in South China

• Published in: Chinese science bulletin Vol. 52; no. 3; pp. 367 - 379
• Main Authors: Peng, XiaoTong, Zhou, HuaiYang, Wu, ZhiJun, Jiang, Lei, Tang, Song, Yao, HuiQiang, Chen, GuangQian
• Format: Journal Article
• Language: English
• Published: Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 01.02.2007
• Subjects: Cyanobacteria; 光养微生物; 华南地区; 富硅温泉; 生物矿化作用; 藻青菌; China, People's Rep; EPS; sheath; biomineralization; hot spring; microbial mats; cyanobacteria
• ISSN: 1001-6538; 1861-9541
• DOI: 10.1007/s11434-007-0042-2

Microbial mats in two hot springs in South China were sampled for the research of mineralization of microbes and its mechanism by the methods of geology and modern biology. The results show that hot spring microbes have the key capability for enrichment of Si, Al, Fe, Ca and other elements, and the microbes are also crucial for the formation of SiO2, CaCO3, clay and so on. The extracellular polymeric substances （EPS） play important roles in the process of mineralization of hot spring microbes, which mainly takes place in the layer of EPS outside cell wall or sheath of cyanobacteria. The sheath outside cell wall, which keeps the normal metabolism of cyanobacteria during the process of mineralization on its surface, is also considerable for the biomineralization of cyanobacteria. According to structure and mineralization characteristics of two microbial mats, the process of mineralization can be divided into three stages, namely, early surface mineralization, middle degradation mineralization, and late desquamation of mineral. The above conclusions are significant for comprehension of the process of mineralization, the process of deposition and the preservation of microfossil in modern and ancient extreme environments.