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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).
PHA Granule-Associated Proteins and Their Diverse Functions
Published in Martin Koller, The Handbook of Polyhydroxyalkanoates, 2020
Mariela P. Mezzina, Daniela S. Alvarez, M. Julia Pettinari
Several types of phasin families have been distinguished based on the presence of different protein motifs that were defined by comparing a great number of phasins found in bacteria belonging to many taxonomic groups. The Pfam database (http://pfam.xfam.org/) considers four phasin-related families, each containing a characteristic domain. The largest family (PF09361) groups sequences found in bacteria that belong to alpha-, beta-, and gammaproteobacteria, including the most studied phasin, PhaP1 from C. necator. Phasins found in Bacillus species comprise a separate family (PF09602), and another (PF09650) contains a diverse group of mostly uncharacterized proteins belonging to different Proteobacteria. The last family (PF05597) includes all characterized phasins belonging to Pseudomonas that accumulate medium-chain-length PHA (mcl-PHA), such as PhaF and PhaI from P. putida, but also contains other proteins from different Proteobacteria [46]. Although most known phasins can be classified in one of these four groups, there is a handful that does not contain any of the identified phasin-related domains, such as GA14 from R. ruber, the first phasin identified [8]. This is also the case of phasins from cyanobacteria, such as PhaP from Synechocystis sp. PCC 6803 [35] and those from Archaea [47]; it is possible that the discovery of new phasins in related microorganisms could, in the future, constitute new phasin families.
Microbial Capacities for Utilization of Nitroaromatics
Published in Ram Chandra, R.C. Sobti, Microbes for Sustainable Development and Bioremediation, 2019
Asifa Qureshi, Hitesh Tikariha, Hemant J. Purohit
Many species of bacteria have proven their ability as potent candidate for NAC degraders, which mainly include Pseudomonas, Burkholderia, Rhodococcus, Roseivirga, and Shewanella oneidensis (Tikariha et al. 2016, Sengupta et al. 2015, Yanzhen et al. 2016, Xu et al. 2016, Selvaratnam et al. 2016, Liu et al. 2017, Min et al. 2016, Ghosh et al. 2017) (Table 11.1, Figure 11.4). Most of these bacteria belong to phyla Proteobacteria and class Gammaproteobacteria, viz., Pseudomonas, Burkholderia, Bradyrhizobium, Cupriviadus, Shewanella, Raoultella. Only a few exceptions such as Roseivirga belonging to Actinobacteria and Rhodococcus belonging to phyla Bacteriodetes exist. Thus, nitroaromatic-utilizing genera fall in those groups of bacteria, which are observed mostly in soil and often associated with the degradation of a varied range of aromatic compounds.
Impact of Oil-Spill Contamination on a Soil Bacterial Community: A 40-Year History of Rehabilitation in the Arava Valley
Published in Soil and Sediment Contamination: An International Journal, 2018
Ruben Girsowicz, Oksana Koryachenko, Chen Sherman, Einav Mayzlish-Gati, Tirza Doniger, Yosef Steinberger
Significant changes in the Gammaproteobacteria bacterial populations between contaminated and non-contaminated samples were found. Gammaproteobacteria is a known oil-degrading microorganism (Kostka et al., 2011). As expected, the Gammaproteobacteria was more abundant in the polluted samples of 1975 compared with the polluted samples of 2014, and coincided with a decrease in Alphaproteobacteria and Betaproteobacteria, indicating that it is most suited to the new contaminated environment. The class Gammaproteobacteria is known for its presence in widespread oil contaminants; however, little is known about its role in the biodegradation processes (Meeboon et al., 2017).
Isolation and characterization of an algicidal bacterium against the bloom-forming algae raphidophyte Heterosigma akashiwo
Published in Environmental Technology, 2023
Zhenzhen Zhang, Junyue Wang, Guangwei Hu, Jinwang Huang, Lei Chen, Yue Yin, Yuefeng Cai, Xin Shen, Nanjing Ji
To control HABs, several studies have focused on the isolation and classification of algicidal bacteria. Here, a bacterial strain (LD-B1) with strong algicidal activity against H. akashiwo was isolated. This strain belonged to the genus Pseudoalteromonas, which is a subclass of the Gammaproteobacteria. The members of the genus Pseudoalteromonas are among the most frequent and widespread algicidal microorganisms [18]. Several studies have documented the ability of these bacteria to lyse phytoplankton, including Raphidophyceae, Dinophyceae, and Bacillariophyceae [36–38]. For instance, Lovejoy et al. (1998) reported that Pseudoalteromonas strain Y possessed strong algicidal activity against several HAB species, including Gymnodinium catenatum, Chattonella marina, and H. akashiwo [37]. Additionally, Pseudoalteromonas strain S1, which exerted strong algicidal effects against the dinoflagellate Akashiwo sanguinea, was isolated from Dapeng Bay, China [36]. Algicidal bacteria are known to inhibit the growth of target algae through two main strategies. Direct attack requires physical contact between the algicidal bacteria and algal cells in order for the target species to be successfully lysed. In contrast, bacterial strains may also lyse the target algae by secreting algicidal components to the extracellular environment, which is generally considered an indirect mode [39,40]. In the present study, the filtrate of strain LD-B1 showed strong algicidal activity against H. akashiwo. This result indicated that the algicidal activity of strain LD-B1 was mediated by extracellular compounds. These findings were consistent with a previous study that reported that Pseudoalteromonas sp. lysed target algae mainly through excreted chemical algicidal substances [18]. However, the detailed algal-lytic mechanism of these compounds needs future study. Additionally, our findings indicated that the algicidal compounds of strain LD-B1 were heat tolerant and stable under acidic conditions, suggesting that the compounds were likely not proteinous. Generally, further researches will be needed to identify the algicidal compounds of strain LD-B1, and to determine the algal-lytic mechanism as previously described [23,24].