PCR-DGGE技术分析不同染料对厌氧污泥中微生物群落结构的影响

Analysis on influence of different dyes on decolorization of microbial community in anaerobic sludge by PCR-DGGE

为了揭示在生物法处理印染废水过程中废水所含染料种类的变化对厌氧脱色菌群群落结构的影响,采用8种不同的染料进行浓度梯度驯化从厌氧污泥中富集得到的脱色菌群,测定了驯化后菌群对其驯化染料的脱色率,并将获得的各个菌群基因组DNA以细菌16S rDNA V3区通用引物进行PCR扩增,将扩增产物进行变性梯度凝胶电泳(DGGE),获得菌群的基因组DNA特征指纹图谱。脱色试验结果显示,经偶氮染料驯化后的菌群对其驯化染料的脱色率要高于经蒽醌染料驯化的菌群。DGGE图谱表明经不同染料驯化后,菌群结构发生了显著变化,其中菌群经活性黑5和酸性蓝127驯化后菌种数减少明显。另外,对菌群的12条优势菌条带进行克隆测序,通过Blast比对,它们分别属于乳杆菌属(Lactobacillus)、肠球菌属(Enterococcus)、乳球菌属(Lactococcus)和双歧杆菌属(Bifidobacterium),在菌群对染料的脱色过程中发挥了重要作用。

In order to reveal how different dyes in printing and dying wastewater influenced the microbial community in anaerobic sludge, eight kinds of dyes were used to domesticate the anaerobic decolorizing microbial community enriched from the anaerobic sludge. The decolorizing abilities of eight different domesticated microbial communities were studied.The DNA of eight domesticated microbial communities was extracted and amplified, and denaturing gradient gel electrophoresis（DGGE） was applied to obtain the DNA fingerprint profile of those microbial communities. The results of the decolorizing experiment showed that the decolorizing rates of microbial communities domesticated by azo dyes were higher than those of microbial communities domesticated by anthraquinone dyes. The DNA fingerprint profile indicated that the structure of the enriched decolorizing microbial community changed after it was domesticated by different dyes. There were fewer bacterial species left after the enriched community was domesticated by Reactive Black 5 and Acid Blue 127. The results of sequencing 12 dominant bands revealed that they respectively belonged to Lactobacillus, Enterococcus,Lactococcus and Bifidobacterium and they could play important roles in the process of decolorization.