生物浸矿反应器中的微生物种群结构及其中可培养微生物的特征

Microbial diversity and characteristics of cultivable microorganisms in bioleaching reactors

摘要:

摘要：【目的】本文旨在了解生物浸矿反应器中的微生物种群结构及其中可培养微生物的特征。【方法】通过构建微生物冶金反应器中矿浆原样的16S rRNA 基因文库，测定16S rRNA基因序列, 分析矿浆中种群结构。同时在不同培养条件下，对样品进行富集培养，分离获得纯菌株；并对各个菌株的16S rRNA基因序列，生理生化特征及对不同矿物的氧化能力进行了分析。【结果】研究中所选生物浸矿反应器中主要的微生物物种有细菌：Leptospirillum sp.，Sulfobacillus sp.，Acidithiobacillus sp.，Spingomonas sp.及古菌Sulfolobus sp.，Ferroplasma sp.等菌属。同时分离出5株纯菌株，这些菌分别与Acidithiobacillus thiooxidans，Acidithiobacillus caldus, Acidithiobacillus ferrooxidans，Leptospirillum ferriphilum，Sulfobacillus thermosulfidooxidans相似。分离获得的菌株具有氧化硫或二价铁和不同硫化矿的能力。【结论】生物浸矿反应器是个微生物种类相对简单的生境，利用非培养和培养技术全面地了解生物浸矿体系中的微生物群落及其生理、浸矿特性，有利于洞察生物浸矿过程中微生物种群结构，强化控制种群组成及浸矿活性，从而提高生物湿法冶金的效率。

Abstract:

Abstract: [Objective] In order to study the microbial diversity and the characteristics of cultivable microorganisms in bioleaching reactors. [Methods] Both conventional culture technique and analysis of a 16S rRNA sequence library were used. The pure cultures were isolated by enriching the samples under different cultural conditions. The morphology characters, physiology and biochemistry characters, genetic characters and oxidation efficiency to different minerals of cultured isolates were analyzed. [Results] The microbial community in bioleaching reactors identified through the gene clone libraries were closely related to bacteria including Leptospirillum sp., Sulfobacillus sp., Acidithiobacillus sp., Spingomonas sp. and Archaea including Sulfolobus sp., Ferroplasma sp. Five strains were isolated after enriching and culturing, which were corresponding to Acidithiooxidians caldus, Acidithiooxidians thiooxidans, Acidithiooxidans ferrooxidans, Leptospirillum ferriphilum and Sulfobacillus thermosulfidooxidans. These isolates could oxidize sulfur or Fe2＋and different sulfide ores. [Conclusion] The bioleaching reactors were dominated by a small number of microbial species that were commonly found at thermoacidophilic environments.