Department of Microbiology, Faculty of Pharmacy, University of Granada, Granada, Spain.
ISME J. 2010 Jul;4(7):922-32. doi: 10.1038/ismej.2010.17. Epub 2010 Feb 25.
Although diverse microbial metabolisms are known to induce the precipitation of carbonate minerals, the mechanisms involved in the bacterial mediation, in particular nucleation, are still debated. The study of aragonite precipitation by Chromohalobacter marismortui during the early stages (3-7 days) of culture experiments, and its relation to bacterial metabolic pathways, shows that: (1) carbonate nucleation occurs after precipitation of an amorphous Ca phosphate precursor phase on bacterial cell surfaces and/or embedded in bacterial films; (2) precipitation of this precursor phase results from local high concentrations of PO(4)(3-) and Ca(2+) binding around bacterial cell envelopes; and (3) crystalline nanoparticles, a few hundred nanometres in diametre, form after dissolution of precursor phosphate globules, and later aggregate, allowing the accretion of aragonite bioliths.
尽管已知多种微生物代谢物能诱导碳酸盐矿物的沉淀，但有关细菌介导作用（尤其是成核作用）的机制仍存在争议。对 Chromohalobacter marismortui 在培养实验早期（3-7 天）沉淀文石的研究及其与细菌代谢途径的关系表明：（1）在细菌细胞表面和/或嵌入细菌膜上沉淀无定形 Ca 磷酸盐前体相之后发生碳酸盐成核；（2）该前体相的沉淀是由于细菌胞外被周围局部高浓度的 PO(4)(3-)和 Ca(2+)结合所致；以及（3）在溶解前体磷酸盐球后形成几百纳米直径的纳米晶颗粒，然后聚集，从而使文石生物岩的堆积得以进行。
