17β-雌二醇污染对微生物甲烷氧化功能的影响

Impact of 17β-estradiol Contamination on the Microbial Methane Oxidation Functions in Water

构建实验室模拟水体微生态系统,运用PCR-DGGE手段,分析17β-雌二醇污染对水体微生物的甲烷氧化功能的影响规律。实验表明,质量浓度为2 000 ng/L的17β-雌二醇污染,对甲烷氧化速率具有一定的促进作用,而质量浓度为4 000~12 000 ng/L的17β-雌二醇污染对甲烷氧化速率具有一定的抑制作用,且其抑制作用与污染浓度存在正线性相关。各污染浓度,在24 h时微生物均出现了应激反应,对甲烷氧化速率产生了抑制,而后所有浓度组甲烷氧化速率均有所回升,最后趋于稳定,且最终的稳定值也与17β-雌二醇污染浓度呈现剂量抑制效应。在不同的污染浓度下,污染浓度越高,污染时间越长,17β-雌二醇对于甲烷氧化菌种群结构的影响越明显。

To analyze the effects of 17β-estradiol （E2） on the function of methane-oxidizing bacteria in aquatic environment,simulatedmicroecosystems has been built and Polymerase ChainReaction-DenaturingGradient Gel Electrophoresis （PCR-DGGE）hasbeenused.Theresultsshowedthat ,underE2concentrationof2000ng/L,methaneoxidationratehadacertainpromotion.Under4000- 12 000 ng /L, it played an inhibiting role, which hada positive linear correlation with the concentration of E2. At 24 h, methaneoxidation rate appeared inhibition in every concentration, then all of them rebounded, and finally stabilized. The final stable rates ofmethane oxidation showed a dose-inhibition effect with E2 concentration. Further more, E2 leaded to changes in the populationstructure of methane oxidizing bacteria. However, these changes did not significant effect the dominant strain. Because each groupshada high similarity, and finally formed stable ecosystems.Under different pollution concentrations,the higher the pollutionconcentration, the longer thepollutiontime ,themore obvious the effect.