Department of Environmental Engineering and Biotechnology, Myongji University, Yongin 449-728, Republic of Korea.
J Microbiol. 2009 Dec;47(6):686-92. doi: 10.1007/s12275-009-0279-3. Epub 2010 Feb 4.
An arsenite (As[III])-oxidizing bacterium, SDB1, was isolated from mine tailing collected from the Sangdong mine area in Korea and showed chemolithotrophic growth on As[III] and CO(2) as the respective electron and carbon sources. SDB1 is Gram-negative, rod-shaped, and belongs to the Sinorhizobium-Ensifer branch of alpha-Proteobacteria. Growth and As[III] oxidation was enhanced significantly by the presence of yeast extract (0.005%) in minimal salt medium containing 5 mM As[III]; decreasing the doubling time from 9.8 to 2.1 h and increasing the As [III] oxidation rate from 0.014 to 0.349 pmol As [III] oxidized cell(-1) h(-1). As[III] oxidation nearly stopped at pH around 4 and should be performed at pH 7 approximately 8 to be most effective. SDB1 was immobilized in calcium-alginate beads and the oxidation capacity was investigated. Specific As[III] oxidation rates obtained with SDB1 (10.1-33.7 mM As[III] oxidized g(-1) dry cell h(-1)) were 10 approximately 16-times higher than those reported previously with a heterotrophic bacterial strain (Simeonova et al., 2005). The stability and reusability of immobilized SDB1 strongly suggested that the immobilized SDB1 cell System can make the As[III] oxidation process technically and economically feasible in practical applications.
一种亚砷酸盐（As[III]）氧化细菌 SDB1 从韩国 Sangdong 矿区采集的尾矿中分离出来，以 As[III]和 CO(2)分别作为电子和碳源进行化能自养生长。SDB1 为革兰氏阴性、杆状，属于α变形菌中的中华根瘤菌-快生根瘤菌分支。在含有 5mM As[III]的最小盐培养基中，酵母提取物（0.005%）的存在显著促进了 SDB1 的生长和 As[III]氧化；将倍增时间从 9.8 小时缩短至 2.1 小时，并将 As[III]氧化速率从 0.014 增加至 0.349 pmol As[III]氧化细胞(-1)h(-1)。As[III]氧化在 pH 约 4 时几乎停止，为了达到最佳效果，应在 pH 7 左右进行。SDB1 被固定在海藻酸钙珠中，并研究了其氧化能力。用 SDB1 获得的特定 As[III]氧化速率（10.1-33.7mM As[III]氧化 g(-1)干细胞 h(-1)）比以前用异养细菌菌株（Simeonova 等人，2005 年）报道的速率高 10 到 16 倍。固定化 SDB1 的稳定性和可重复使用性强烈表明，固定化 SDB1 细胞系统可以使 As[III]氧化过程在实际应用中在技术和经济上都具有可行性。
