海洋产脲酶细菌的筛选及诱导形成碳酸钙矿物的特征

产脲酶细菌普遍存在于自然界,其对碳酸钙的矿化作用被广泛用于工程地质和环境等各项工程领域;本研究旨在从北戴河新河河口海洋沉积物中分离产脲酶细菌,探讨其诱导形成碳酸钙的特征,为地质与工程领域的应用提供良好的材料.从海洋沉积物样品中共分离出33株细菌,经筛选,其中有10株细菌具有产脲酶活性,16S rRNA基因序列分析表明:...

Screening of Marine Urease-producing Bacteria and Characterization of Their Produced Calcium Carbonate Minerals

Urease-producing bacteria are widespread in nature, and the calcium carbonate biomineralization induced by these bacteria are widely used in various geological and engineering fields. This study aims to isolate the urease-producing bacteria from marine sediments, and to characterize the produced calcium carbonate crystals. The results may have potential applications in the geological and engineering fields. A total of 33 bacterial strains were isolated from the marine sediments sampled from Beidaihe (China), among which 10 bacterial strains were identified to produce urease. The 16S rRNA gene sequence analyses show that three strains belong to the Ochrobactrum genus, and the other seven strains belong to the Lysinibacillus genus. Two strains, O. anthropic CP57 and L. fusiformis CP66, were selected to characterize their calcium carbonate formations. The SEM, XRD, and SAED results show that the calcium carbonate formed by CP57 is irregular-shape calcite, whereas that formed by CP66 is irregular-shape or spherical calcite and vaterite. Further FTIR characterization of the bacterial calcium carbonate shows that the spectrum of CP57 at the wave numbers of 1,422 cm^-1, 711 cm^-1 and 875 cm^-1, correspond to the typical absorption peaks of calcite. However, exception appears in the FTIR spectrum of CP66, with two extra peaks at 1,081 cm^-1 and 743 cm^-1 clearly attributed to vaterite. Our results provide a foundation to reveal the mechanism of different morphologies and mineral phases formed by various bacteria.