Bacterial community structure in waterlogged bamboo slips excavated from the Laoguanshan Han Dynasty Tomb of Chengdu北大核心CSCD

To investigate the bacterial community structure features of soak solutions used to preserve bamboo slips that were excavated from Han dynasty tomb located in Laoguanshan of Chengdu and to reveal the diversity of bacteria in these soak solutions, PCR-DGGE was employed. Subsequently, the major DGGE bands were excised and sequenced to analyze the phylogeny of bacteria. The richness (S), Shannon-Wiener index (H), and Simpson index (D) of deionized water (0#) without the soaked bamboo slips were higher than those of the other samples. Among the bamboo slip soak solution samples, there were significant differences in these indicators; the bacterial genetic diversity of sample 121# was the highest and that of sample 1# was the lowest. Principal Component Analysis (PCA) showed that there were comparatively large differences among the samples, and the similarity between sample 1# and others was the lowest. Based on the sequence analysis, the major community of bacteria in soak solution were belonged to Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, including Cupriavidus, Aquabacterium, Comamonas, Albidiferax, Hyphomicrobiaceae, Azospirillum, Nevskia, Streptococcus, Staphylococcus, Sediminibacterium, and Propionibacterium, among which Cupriavidus of the β-Proteobacteria class was detected in all samples. The bacterial community structure of the soak solutions that were collected from different bamboo slips was quite complex and significantly different. The analysis of the main bacterial community revealed the potential bacteria species that may trigger the damage in bamboo slips; the result provided a reference to prevent waterlogged bamboo slips from microbial diseases in the future. © 2018 Science Press. All rights reserved.     

PCR-DGGE研究沸石植生混凝土微生物群落结构

采用PCR-DGGE技术研究了滨水区和非滨水区沸石植生混凝土内部微生物群落结构,结果表明:沸石植生混凝土内部微生物多样性指数和物种丰度值均很高,滨水区和非滨水区植生混凝土内部微生物多样性指数与物种丰度总体持平,但是各部分微生物丰度差异明显.滨水区微生物丰度值根部5~10cm>根部10~15cm>沸石表面生物膜.非滨水区微生物丰度沸石表面生物膜>根部5~10cm>根部10~15cm.基因测序结果和系统发育树分析可知.滨水区和非滨水区以及沸石混凝土内各部分之间优势菌种各不相同,在滨水区,沸石表面微生物膜中优势菌种为丙酸杆菌、都柏林克罗诺杆菌和葡萄球菌属,根部5~10cm中优势菌种为黄杆菌和沙门氏菌属,根部10~15cm中优势菌种为慢生根瘤菌属;非滨水区,沸石表面微生物膜中优势菌种为芽孢杆菌和红假单胞菌属,根部5~10cm中优势菌种为沙门氏菌、微球菌亚目的Agromyces和酸杆菌属,根部10~15cm中优势菌种为沙门氏菌属.     

菲和铬(Ⅵ)单一及复合暴露对土壤微生物多样性的影响

有机物和重金属已成为我国土壤环境中常见的2类污染物质,二者间复合污染引起的土壤生态环境风险不容忽视。本研究以多环芳烃模式物菲和典型重金属铬(VI)作为受试物质,采用PCR-DGGE分子指纹图谱技术,探讨这2种污染物单一及复合暴露对土壤微生物群落多样性的影响,并选用主成分分析、聚类分析和戴斯系数3种算法对微生物群落相似性进行了比较。结果表明,在暴露实验第1天,菲单一暴露低浓度组中微生物群落相似性产生了极为明显的变化,而到第7天时,菲和铬(VI)单一暴露高浓度组均对微生物群落结构相似性产生最大程度的影响;采用香农指数法评价微生物群落的多样性,发现在暴露实验第7天,菲和铬(VI)单一暴露高浓度组对微生物群落多样性的影响比复合暴露高浓度组更强,二者复合暴露的相互作用方式表现为拮抗效应。本研究证明低浓度菲短期暴露的效应高于高浓度暴露结果,因而多环芳烃菲自身及其在复合暴露中所扮演的角色尤其值得关注。     

应用于PCR-DGGE分析的活性污泥微生物总DNA提取方法比较

探讨适用于PCR-DGGE分析研究的活性污泥细菌和真菌的DNA提取方法。采用5种方法提取活性污泥微生物基因组DNA,以DNA纯度、含量、片段大小及DGGE条带多样性作为考察指标评价提取方法的优劣,以确定最佳实验方案。紫外吸收法和琼脂糖凝胶电泳结果显示,试剂盒法提取的DNA含量最低,其余4种方法获得的DNA含量无显著差异,就DNA纯度而言,试剂盒法最优;除高温裂解法对真菌细胞壁裂解效果较差外,其他4种方法均能不同程度地裂解细菌和真菌细胞;DGGE结果表明,高温裂解法获得的细菌条带最多,基于SDS的细胞裂解法得到的真菌条带最多。综合分析,高温裂解法更适合于活性污泥中细菌的PCR-DGGE分析,基于SDS的细胞裂解法则更适合于污泥中真菌的PCR-DGGE分析。     

贫营养条件下2种MBR污泥微生物的菌群对比

为了揭示贫营养环境下MBR污泥微生物群落结构的演替和菌群变化的异同,取洗浴再生水、工业再生水MBR的污泥进行周期培养,利用PCR-DGGE和克隆测序技术获得了DNA指纹图谱并建立系统发育树。研究表明,微生物群落结构在贫营养条件下演替明显,洗浴水污泥微生物形成新的优势菌群(Uncultured Pseudomonas)而工业水只维持了原有的部分菌群(Uncultured Sphaerotilus)。2种污泥培养过程中种群多样性变化突出且差异显著。同时洗浴水污泥菌群相似性在培养第8天时发生突变而工业水总体变化平缓。克隆测序表明2种MBR污泥中既有与贫营养环境适生的共性种属又有与各自来源相对应的特性种属。菌群特异性与废水来源紧密相关,是造成2种污泥对贫营养环境适应能力不同的根本原因。     

PCR-DGGE技术解析A2/O工艺好氧单元中微生物群落结构

应用PCR-DGGE方法,追踪了汉沽工业废水处理中好氧工艺的活性污泥系统中微生物群落结构动态变化过程及其微生物群落结构组成。研究结果表明:系统中的微生物群落结构随水质变化而变化,随着培养时间的延长,微生物群落结构趋于稳定,分别属于5大类群,与γ、δ、α、ε变形杆菌(Proteobacterias)、芽孢杆菌(Bacilli)的亲缘关系较近。其中γ变形杆菌是该废水处理过程中的主要菌群,包括Pseudomonas sp.、Rheinheimera sp.、Citrobacter sp.、Klebsiella sp.、Enterbacte-riaceae、Stenotrophomonas maltophilia、Acinetobacter。在整个系统中uncultured Pseudomonas sp.、Halobacillus sp.、Pseudomonassp.、Pseudomonas stutzeri、Acinetobacter sp.可稳定存在于系统中,为该污水处理系统中的优势微生物。因此,提高Halobacillussp.、Pseudomonas sp.、Pseudomonas stutzeri、Acinetobacter sp.菌属在系统中的数量和质量,有利于提高废水生化处理的效果。     

A+OSA污泥减量工艺的微生态特性

采用16S rDNA序列与PCR-DGGE(polymerase chain reaction-denaturing gradient gel electrophoresis)分析技术相结合的方法,研究了A+OSA(the anoxic+oxic-settling-anaerobic)污泥减量工艺在不同工况下的减量效果及其微生态特性。结果显示,在自然条件下,A+OSA工艺可有效减少剩余污泥27%左右。分子生物研究表明,解耦联池的插入可以明显改变系统微生物的群落结构,且随着解耦联池水力停留时间的延长,系统中部分微生物被"淘洗",微生物丰富度和多样性指数均有所降低。相似性分析表明,参照系统和A+OSA工艺分属于2个不同的集群,但在A+OSA工艺内部各反应池样品间具有较高的相似性,且各反应池在HRT为5.16 h和7.14 h时,表现为显著相似。通过上述研究可为该工艺优化及调控提供理论指导。     

Spatial characteristics analysis by PCR-DGGE for bacterial communities in surface sediments of Tangxi River,Hefei City北大核心CSCD

Microbes play an important role in material circulation and pollutant release in urban sediments, and its community structure can provide an important basis for evaluating the pollution load and ecosystem health of an urban river. In this study, bacterial communities in sediments from different locations of Tangxi River in Anhui Province were analyzed and compared, with an objective of evaluating the effects of aquatic environment on spatial characteristics of bacterial communities and the feasibility of using bacterial community composition as an indicator of urban river health. PCR-DGGE was applied to analyze the bacterial communities; fifteen major bands of 16S rDNA genes fragments from DGGE profiles of sediment samples were further eluted from gel, reamplified and sequenced. The sequences of these fragments were compared with the database in GenBank (NCBI). The collected samples were clustered based on UPGM Aanalysis. In addition, relationships between bacterial communities and environmental factors were analyzed by Monte Carlo test and redundancy analysis (RDA). The DGGE profiles indicated that upstream surface sediments had about 30 bands, but the differences in brightness were not significant. Although midstream surface sediments had only 18 bands on average, the brightness of some bands was relatively high, indicating that some dominant species of bacteria existed in these sediments. The amounts of bands in downstream sediments were between those of upstream and midstream, with some bands of high brightness. The NCBI comparison results showed that ten sequences shared 98-100% homology with known sequences, one with 97%, and the other four with uncultured bacteria. Shannon index (H) of bacterial diversity from upstream surface sediments was 3.31 on average, which was significantly (P < 0.05) higher than that of midstream surface sediments, and slightly higher than that of downstream surface sediments. UPGMA results showed both the distribution of bacteria communities and the diversity were strongly related with the sampling locations (Eigenvalue = 0.188, P = 0.134). Monte Carlo test and RDA analysis showed that the ion exchangeable form of nitrogen (IEF-N) was the main factor influencing the spatial characteristics of bacterial communities in the sediments. The aquatic plants had a significant effect on the richness of bacterial communities in the sediments, and the effectiveness of plant species was more notable than that of the vegetation coverage. The above results indicated that bacterial community structure and diversity in the surface sediments can well reflect the degree of urbanization development and effectiveness of ecological restoration in Tangxi River region.     

间歇好氧硫酸盐废水处理系统微生物区系解析

应用PCR-DGGE(polymerase chain reaction-denaturing gradient gel electrophoresis)技术和16S rDNA序列测定对间歇好氧硫酸盐废水处理工艺的微生物群落结构进行了研究.采集味精厂好氧池原始污泥以及实验室内间歇好氧工艺驯化后不同条件下的活性污泥样品,通过基因组DNA的提取、PCR扩增和DGGE分离,初步分析了各污泥样品的微生物群落多样性,结果表明,PCR-DGGE方法可以在一定程度上反映工艺以及操作条件对微生物群落结构的影响.通过DGGE反复分离纯化及割胶回收,DGGE检验为单一条带后进行测序并提交到GenBank数据库比对,结果表明,间歇好氧硫酸盐系统中优势菌株大多数为未培养细菌,来源于不同的污染环境,具有重要污染物降解的生态功能,其中包括与硫酸盐还原菌(Desulfobulbus propionicus)在系统发育上非常接近的菌株.     

生物膜水解-好氧循环系统处理活性艳蓝RB-19的微生物群落动态变化

为了研究生物膜水解-好氧循环系统处理蒽醌类染料活性艳蓝RB-19效果及其中微生物群落动态变化,利用基于16S rDNA的PCR-DGGE技术获得了微生物群落的DNA特征指纹图谱。结果表明,该系统能有效地降解活性艳蓝RB-19模拟废水,在RB-19浓度≤400 mg/L时,RB-19去除率维持在82%～96%之间,COD去除率维持在95%左右,但当RB-19浓度提高到500 mg/L时,RB-19去除率降低到58%,COD去除率降低到85%。DGGE分析表明,生物膜上的微生物群落结构随着RB-19浓度递增有显著变化,好氧、水解反应器内的细菌Shannon指数分别从1.32和1.20降低到1.11和1.19。UPGMA聚类分析和NMDS散点分析表明,水解、好氧反应器内的微生物并没有因为同处一个系统内而使得其菌群落结构产生明显的趋同倾向。系统内的多种优势菌群为兼性细菌,克隆测序的结果发现,在水解反应器存在一类具有很强还原能力的古细菌——Methanobacterium sp.MB4。