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Microbial Control during Hydraulic Fracking Operations
Published in Kenneth Wunch, Marko Stipaničev, Max Frenzel, Microbial Bioinformatics in the Oil and Gas Industry, 2021
Renato De Paula, Irwan Yunus, Conor Pierce
Comparison of the metabolic profiles of microbial communities in hydraulic fracturing source water and produced water from the Marcellus Shale further underscore the importance of utilizing an effective preservative. While the source water bacteria are composed predominantly of aerobic Alphaproteobacteria, the produced water contained a majority of anaerobic Gammaproteobacteria capable of metabolizing sulfur compounds to sulfide. Initial biocide treatment would reduce the microbial count in the source water, but without use of a preservative the reservoir communities would increase risks associated with H2S and FeS such as infrastructure corrosion, souring, and operator safety. This same study also found that the microbial communities in produced water showed an increased genetic ability to handle stress, making management of that water for reuse or disposal through disinfection more difficult when reservoir growth is uncontrolled (Mohan et al., 2014).
Contribution of culture-independent methods to cave aerobiology: The case of Lascaux Cave
Published in Cesareo Saiz-Jimenez, The Conservation of Subterranean Cultural Heritage, 2014
P.M. Martin-Sanchez, C. Saiz-Jimenez
A total of 83 high-quality sequences from 96 sequenced clones were used for this clone library. Rarefaction curves were performed for estimating the bacterial diversity (Fig. 1a). These curves trended towards a plateau detecting only fourteen OTUs at 5% of evolutionary distance. Therefore, enough clones were studied to reliably characterise the major bacteria. The majority of bacterial clones corresponded to the Gammaproteobacteria class (91.6% of total clones), followed by the Alphaproteobacteria class (7.2%) and the Actinobacteria phylum (1.2%) (Table 2).
Application of Omic Tools for Microbial Community Structure and Function Analysis
Published in Maulin P. Shah, Wastewater Treatment, 2022
Hiren K. Patel, Divyesh K. Vasava, Hiren N. Bhalani, Rishee K. Kalaria
The research by 16S-RFLP review of bacterial populations from seven pulp and paper wastewater treatment systems was carried out. Group coefficients of similarity were focused on quantitative determination of both the locations of the DNA bands and the band intensities in order to compare relative population differences, and a dendrogram was created for all mills. Samples are usually made up of individual clusters from each mill. From this dendrogram is an extracted similarity with and within mills, i.e., the node similarity in which all samples from one mill converge and describe similitude inside a mole. The resemblance of 16S-RFLP profiles from mills has been partly attributed to wood furnishing (Baker et al., 2003). This approach was not adequately sensitive to distinguish deviations from various places or from different sample periods inside the mill treatment scheme. Gilbride and Fulthorpe (2004) later conducted R-FLP research to compare and contrast microbial populations of 10 pulp and paper mill environments, on both whole ecosystems and individual cultivated isolates. Both groups exchanged 60% of their pattern of DNA bands. The 16S rRNA genes were described in partial sequences from the cultivable isolates of Ancylobacter aquaticus, Blastobacter sp., Comamonas sp., Klebsiella sp., Bacillus spp., Pseudomonas spp., and Xanthobacter sp. The structure of the bacterial culture, functional stability, and N2 fixation were studied at the pilot plant. DNA was isolated and obtained from wastewater treatment for pulp and paper-activated sludge tests and amplified up to 1.5 kb. Previously acquired clones have been separated by RFLP from the restrictive enzyme HhaI (Amersham). Fragment analysis was performed with the automatic DNA sequencer 377-XL of the Applied Biosystems, and the sizes of the 5′ T-RFs and the intensities of their fluorescent emission signals (peak area) were determined with the GelCompar II program. The structure of the bacteria was controlled by Alphaproteobacteria and Betaproteobacteria, with less bacterial phylum Bacteroidetes (Reid et al., 2008).
Forward osmosis membrane bioreactor using Bacillus and membrane distillation hybrid system for treating dairy wastewater
Published in Environmental Technology, 2021
At the genus level, Pirellula and Hyphomicrobium dominated the Bacillus sludge (sludge B) at the beginning of the test, as shown in Figure 5. Pirellula, in the phylum Planctomycetes, are facultative aerobic chemoheterotrophic bacteria that can use ammonia and perform heterotrophic nitrification [29]. Planctomycetes are important for the carbon and nitrogen cycles in oceans. A feature that sets Pirellula apart from other microbes is many sulfatases encoded in the genome. These sulfatases can degrade sulfated glycopolymers that are abundant in marine snow. Hyphomicrobium, in the order Rhizobiales and class Alphaproteobacteria, are aerobic chemoorganotrophic bacteria that perform aerobic denitrification [30]. Gp1, in the phylum Acidobacteria, was dominant in the sludge B1 at the end of the test. Acidobacteria have recently been isolated and defined as oligotrophic bacteria [31]. Membrane fouling at the end of the test caused a low FO water flux, which decreased the influent organic loading, and thus led to the environment becoming oligotrophic. Oligotrophic bacteria are tolerant and play important roles in the nitrogen cycle. For example, oligotrophic bacteria accounted for 74% of the total denitrifying bacteria isolated by Hashimoto [32]. Acidobacteria can also acclimatize to the saline environment [33]. Importantly, Bacillus increased the Gp1 abundance [34].
Effect of ammonium to nitrite ratio on reactor performance and microbial population structure in anammox reactors
Published in Environmental Technology, 2020
Nomalanga P. Gasa, Chika F. Nnadozie, Kiprotich Kosgey, Faizal Bux, Sheena Kumari
Within the phylum Proteobacteria, the abundance of Betaproteobacteria were high for all the different ammonium to nitrite ratio. Betaproteobacteria (phylum to which AOB belong) are responsible for oxidation of ammonium to nitrite (first step of nitrification process) [35]. A similar observation was observed for another Proteobacteria class Alphaproteobacteria. Alphaproteobacteria with known genera Nitrobacter and Nitrococcus (affiliated with NOB) are also responsible for the second step of nitrification that is the oxidation of nitrite to nitrate [35]. Members of Anaerolineae (belong to Chloroflexi) and Saprospira are generally associated with anammox bacteria and involved in the degradation of anammox metabolic by-products and complex organic materials [36]. Alpha diversity and similarity indexes (Bray Curtis and Jaccard index) values did not differ amongst the reactors. These suggest that the abundances of the microbial population differed with different substrate ratios (Figures 7 and 8), but the diversity remained similar.
Ibuprofen biodegradation by hospital, municipal, and distillery activated sludges
Published in Environmental Technology, 2020
Huang CY, Fu LH, Sung MH, Huang CF, Wu JP, Kuo HW
Currently, three microbial strains including Nocardia sp. NRRL 5646 [30], Sphingomonas sp. Ibu-2 [1,31], and Variovorax sp. Ibu-1 [2] had been isolated and noticed capable of IBU degradation. Nocardia sp. belongs to Nocardiaceae family, Actinobacteria order, Actinobacteria class of the Actinobacteria phylum. The Sphingomonas sp. belongs to Sphingomonadaceae family, Sphingomonadales order, Alphaproteobacteria class of the Proteobacteria phylum; and, the Variovorax sp. belongs to Comamonadaceae family, Burkholderiales order, Betaproteobacteria class of the Proteobacteria phylum. Besides, in reactors used for IBU biodegradation aerobically, Comamonas aquatica and Bacillus sp. had also been identified as parts of the indigenous bacterial community [45].