Wan Wen-Jie, Xue Zhi-Jun, Zhang Ze-Wen, He Dong-Lan
College of Life Sciences, South-Central University for Nationalities, Wuhan 430070, China.
Huan Jing Ke Xue. 2017 May 8;38(5):2036-2043. doi: 10.13227/j.hjkx.201611103.
Manganese is a common inorganic pollutant, which is difficult to remove from the environment. In this research, a high efficient manganese-oxidizing bacterium sp. HW-16 was isolated from the manganese-rich soil using selective media. Besides, high-throughput sequencing revealed that there were significant differences of the microbial community compositions when bacteria were acclimated in different conditions, and was the dominant genus in Mn(Ⅱ) containing media. In this paper, the microbiological properties of strain HW-16 and Mn(Ⅱ) oxidation mechanism were investigated. The results indicated that the maximal Mn(Ⅱ) tolerance mass concentration of strain HW-16 was 5000 mg·L,and it exhibited a decent Mn(Ⅱ) oxidation efficiency with the highest value of 66.28% at a Mn(Ⅱ) concentration of 3000 mg·L. Single factor experiments demonstrated that environmental factors could affect the growth and Mn(Ⅱ) oxidation efficiency of strain HW-16. At 30℃ or pH 7.0, at 1% or 3% salinity, and at 200 r·min, strain HW-16 got the highest biomass. While the highest Mn(Ⅱ) oxidation efficiency occurred at high temperature (≥40℃), high pH (≥7), high shaking speed and low salinity. Strain HW-16 could oxidize Mn(Ⅱ) by producing Mn(Ⅱ) oxidizing active factor and turn Mn(Ⅱ) into precipitation by synthesizing alkaline metabolites.
锰是一种常见的无机污染物，难以从环境中去除。本研究利用选择性培养基从富锰土壤中分离出一株高效锰氧化细菌HW-16。此外，高通量测序显示，细菌在不同条件下驯化时，微生物群落组成存在显著差异，且在含Mn(Ⅱ)培养基中为优势属。本文对菌株HW-16的微生物学特性及Mn(Ⅱ)氧化机制进行了研究。结果表明，菌株HW-16对Mn(Ⅱ)的最大耐受质量浓度为5000 mg·L，在Mn(Ⅱ)浓度为3000 mg·L时表现出良好的Mn(Ⅱ)氧化效率，最高值为66.28%。单因素实验表明，环境因素会影响菌株HW-16的生长和Mn(Ⅱ)氧化效率。在30℃或pH 7.0、盐度为1%或3%、转速为200 r·min时，菌株HW-16获得最高生物量。而最高Mn(Ⅱ)氧化效率出现在高温(≥40℃)、高pH(≥7)、高振荡速度和低盐度条件下。菌株HW-16可通过产生Mn(Ⅱ)氧化活性因子氧化Mn(Ⅱ)，并通过合成碱性代谢产物将Mn(Ⅱ)转化为沉淀。
