Article
Biotechnology & Applied Microbiology
Pranav P. Kulkarni, Sambhaji B. Chavan, Mandar S. Deshpande, Dhanishta Sagotra, Pramod S. Kumbhar, Anand R. Ghosalkar
Summary: This study focuses on enriching methanotroph dominated mixed microbial community and investigating their ability to produce polyhydroxyalkanoates (PHA). The study found that Methylocystis was the dominant species and nitrate was the preferred nitrogen source for growth and PHA production. Under nitrate limited condition, the mixed culture accumulated a maximum of 22.20% polyhydroxybutyrate (PHB) with a molecular weight of 2.221 x 105 g mol-1 and a polydispersity of 1.82.
JOURNAL OF BIOTECHNOLOGY
(2022)
Article
Microbiology
Kangli Guo, Anna Hakobyan, Timo Glatter, Nicole Paczia, Werner Liesack
Summary: High NH4+ load inhibits bacterial methane oxidation by competing with CH4 for the active site of pMMO. Methylocystis sp. strain SC2 shows cellular acclimatization response to high NH4+ levels involving stress-responsive proteins, synthesis of compatible solutes, and induction of glutathione metabolism pathway. Increased NH4+ load leads to increased pMMO-based oxidation of NH3 to toxic hydroxylamine, resulting in accumulation of NO2- and N2O.
Article
Engineering, Environmental
Ahmed Fergala, Ahmed AlSayed, Ahmed Eldyasti
Summary: The study explores the potential of coupling PHB consumption with methanol production using a PHB accumulating methanotrophic strain. Optimum cultivation conditions play a key role in increasing methanol production for methanotrophs. Cells depending on PHB solely showed improved methanol production when growth, PHB accumulation, and methanol production periods were adjusted. Additionally, PHB-rich cells supplied with 25 mM formate were able to produce a higher methanol concentration than PHB-lacking cells with 100 mM formate.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Environmental Sciences
Sara Cantera, Elisa Rodriguez, Nicolas Santaella Vecchini, Juan Carlos Lopez, Pedro A. Garcia-Encina, Diana Z. Sousa, Raul Munoz
Summary: This study investigated the survival and metabolic mechanisms of methane oxidizing bacteria (MOB) under low methane concentrations. The research found that the activity and energy production of methane oxidation were not lost during starvation periods, and poly-hydroxyalkanoate and nitrification metabolism played important roles in maintaining cell viability of MOB. The genus Methylocystis emerged as a key MOB in environments with diluted and intermittent methane emissions.
ENVIRONMENTAL RESEARCH
(2023)
Article
Microbiology
Julia B. Gontijo, Fabiana S. Paula, Andressa M. Venturini, Jessica A. Mandro, Paul L. E. Bodelier, Siu M. Tsai
Summary: This study described the metagenome-assembled genome (MAG) of Methylocystis sp. from Amazonian floodplains sediments and explored its functional potential and ecological traits. The analysis revealed that it belongs to Methylocystis parvus and has the ability for methane oxidation and nitrogen fixation, as well as unique genes related to nitrogen metabolism and cell motility.
Article
Environmental Sciences
Ashish Kumar Singh, Suraj Prabhakarrao Nakhate, Rakesh Kumar Gupta, Atul Rajkumar Chavan, Bhagyashri Jagdishprasad Poddar, Om Prakash, Yogesh S. Shouche, Hemant J. Purohit, Anshuman Arun Khardenavis
Summary: This study characterized the microbial community at different depths of a landfill to assess their roles as methane sinks. The results showed anaerobic degradation of organic matter in the bottom soil and active aerobic denitrification in the top soil. The top soil had a higher abundance of aerobic methanotrophs, while the bottom soil had a dominance of anaerobic methanogens. The findings provide a better understanding of the relationship between methanotrophs and their environment in landfills.
ENVIRONMENTAL RESEARCH
(2022)
Article
Agricultural Engineering
Ye Rim Park, Shyam Krishna, Ok Kyung Lee, Eun Yeol Lee
Summary: This study investigated the epoxidation efficacy of different types of methanotrophs and found that type II methanotrophs are more efficient in converting alkenes to epoxides. By overexpressing epoxide hydrolases (EHs) of different origins in type II methanotrophs, 1,2-diols were successfully synthesized from epoxides. This demonstrates the potential of using methanotrophs as a microbial platform for diol production and the development of continuous bioreactors for industrial applications.
BIORESOURCE TECHNOLOGY
(2023)
Article
Microbiology
Marina Lazic, Scott Sugden, Dominic Sauvageau, Lisa Y. Stein
Summary: This study investigated the metabolic responses of Methylocystis sp. Rockwell to different combinations of carbon and nitrogen sources. The results showed that methane-ammonium condition resulted in the highest growth, with methane-nitrate condition following closely behind. Furthermore, polyhydroxybutyrate production was higher in methanol-grown cells, regardless of the nitrogen source.
FEMS MICROBIOLOGY LETTERS
(2021)
Review
Biotechnology & Applied Microbiology
Noemi Poma, Andrea Bonini, Federico Vivaldi, Denise Biagini, Mariagrazia Di Luca, Daria Bottai, Fabio Di Francesco, Arianna Tavanti
Summary: Climate change due to increased greenhouse gas emissions has had a significant impact on the sustainability of life on Earth. Methane, a greenhouse gas, is increasing in concentration and its measurement is important for the environment and safety. The use of methane-oxidizing bacteria in biosensing systems shows promise for methane quantification and monitoring.
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
(2023)
Article
Biotechnology & Applied Microbiology
Sara Malvar, Leticia O. B. Cardoso, Bruno Karolski, Elen A. Perpetuo, Bruno S. Carmo, Julio R. Meneghini
Summary: This study investigates the relationship between collective motion and propulsion of bacterial consortia and their biopolymer production efficiency, finding that different consortia exhibit distinct rheological behaviors closely related to their ability to capture methane. The formation of structures in consortia may hinder bacterial movement, impacting biopolymer production.
BIOTECHNOLOGY AND BIOENGINEERING
(2021)
Article
Microbiology
Ekaterina N. Tikhonova, Denis S. Grouzdev, Alexander N. Avtukh, Irina K. Kravchenko
Summary: A novel species of high-affinity methanotrophic bacteria, Methylocystis silviterrae sp. nov., was proposed based on the characteristics of strain FST isolated from forest soil in southern Moscow. FST utilizes only methane and methanol as carbon sources, grows at temperatures of 4-37 degrees C and pH of 4.5-7.5, and possesses genes for nitrogen fixation, polyhydroxybutyrate synthesis, antibiotic resistance, and detoxification of various substances.
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY
(2021)
Article
Environmental Sciences
Jiaqi Wang, Yuxiang Zhao, Meng Zhou, Jiajie Hu, Baolan Hu
Summary: For a long time, it was believed that aerobic methane-oxidizing bacteria were the main consumers of methane in soils. However, the discovery of anaerobic methanotrophs in recent decades has greatly improved our understanding of the methane cycle. This study collected soil samples from different climatic regions to investigate both conventional and novel methanotrophs and found that a dual-core microbial methane sink, consisting of aerobic and anaerobic methanotrophs, was responsible for over 80% of soil methane emission reduction. These findings contribute to reducing uncertainties in the estimation of soil methane emissions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Jasir Jawad, Mohd Junaid Khalil, Anoop Kumar Sengar, Syed Javaid Zaidi
Summary: The study evaluated the performance of a biofilter in predicting methane concentration at different heights and times, and developed a model for this purpose. The model was validated with experimental data and showed that the biofilter could achieve a high removal efficiency.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Review
Environmental Sciences
Qiong Nan, Liqing Xin, Yong Qin, Muhammad Waqas, Weixiang Wu
Summary: This review explores the mechanisms and controversies surrounding the long-term effects of biochar on methane mitigation in paddy soil. It proposes potential mechanisms of biochar in long-term methane emission response and highlights the need for further research in order to achieve carbon neutrality goals.
Article
Soil Science
Cristina P. Fernandez-Baca, Adam R. Rivers, Woojae Kim, Ryo Iwata, Anna M. McClung, Daniel P. Roberts, Vangimalla R. Reddy, Jinyoung Y. Barnaby
Summary: Rice genotype and plant developmental stage significantly influence the soil microbial community structure and methane emissions, suggesting that selecting genotypes with lower methanogen populations and higher methanotroph populations during high methane emitting phases can help reduce methane emissions.
SOIL BIOLOGY & BIOCHEMISTRY
(2021)
Article
Environmental Sciences
Milena Marycz, Anna Brillowska-Dabrowska, Sara Cantera, Jacek Gebicki, Raul Munoz
Summary: The potential of Candida subhashii, Fusarium solani, and their consortium for the degradation of n-hexane, trichloroethylene (TCE), toluene, and alpha-pinene in biofilters and biotrickling filters was systematically evaluated in this study. The results showed that biotrickling filters exhibited superior biodegradation performance compared to biofilters, regardless of the volatile organic compounds (VOCs) tested. Additionally, a more effective VOC biodegradation was observed when C. subhashii and F. solani were grown as a consortium.
Article
Biochemistry & Molecular Biology
Sergio Bordel, Diego Martin-Gonzalez, Raul Munoz, Fernando Santos-Beneit
Summary: This study reports the genome of Bacillus altitudinis B12, a bacterium that efficiently degrades PLA and keratin. The genome analysis revealed the presence of genes encoding keratinase and PLA depolymerase, which explain the biodegradation capability of the strain. This bacterium has potential applications in environmentally friendly biotechnology.
MOLECULAR GENETICS AND GENOMICS
(2023)
Article
Microbiology
Fernando Santos-Beneit, Le Min Chen, Sergio Bordel, Raquel Frutos de la Flor, Octavio Garcia-Depraect, Raquel Lebrero, Sara Rodriguez-Vega, Raul Munoz, Rosa Aragao Borner, Tim Borner
Summary: In recent years, microbial enzymes capable of degrading plastics have been discovered. Biocatalytic depolymerization mediated by enzymes has emerged as a more efficient and eco-friendly alternative for plastic treatment and recycling. However, the systematic study of depolymerase enzymes in degrading a range of plastic polymers is still lacking.
Article
Biotechnology & Applied Microbiology
Paula Bucci, Octavio Garcia-Depraect, Enrique Jose Marcos Montero, Noemi Zaritzky, Alejandro Caravelli, Raul Munoz
Summary: This study developed a self-sustaining microalgal-bacterial granular sludge process for the treatment of industrial wastewater, achieving complete removal of phenol and ammonia. The performance of the microalgal-bacterial system was compared with a conventional aerobic bacterial system, showing similar nitrogen removal efficiency. Higher simultaneous nitrification and denitrification occurred in the aerobic bacterial system, while nitrogen assimilation by the microalgal-bacterial biomass compensated for the lower denitrification activity in the microalgal-bacterial system. The application of the microalgal-bacterial system was found to be more cost-effective and sustainable.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2023)
Review
Multidisciplinary Sciences
Cristian A. A. Sepulveda-Munoz, Ignacio de Godos, Raul Munoz
Summary: Piggery wastewater is characterized by high concentrations of organic matter and ammonium, as well as odour nuisance. Photosynthetic microorganisms such as purple phototrophic bacteria (PPB) and microalgae have been found to be effective in sustainable wastewater treatment using engineered photobioreactors, with low operating costs and efficient recovery of carbon, nitrogen and phosphorous.
Article
Microbiology
Diego Martin-Gonzalez, Sergio Bordel, Selvin Solis, Jorge Gutierrez-Merino, Fernando Santos-Beneit
Summary: Two efficient feather-degrading bacteria, Bacillus sonorensis and Bacillus licheniformis, were isolated from honeybee samples and showed the ability to grow on chicken feathers as the sole carbon and nitrogen sources. B. licheniformis CG1 strain exhibited high keratinase activity and broad pH stability, making it advantageous for various industrial applications. Gene clusters associated with the synthesis of antimicrobial compounds were identified in most Bacillus isolates, with B. licheniformis CG1 containing sequences similar to lichenysin and lichenicidin, which have shown antimicrobial activity against different bacteria. This study highlights the potential of B. licheniformis CG1 for industrial applications such as animal nutrition, leather processing, detergent formulation, and feather degradation.
Article
Microbiology
Diego Martin-Gonzalez, Sergio Bordel, Fernando Santos-Beneit
Summary: In this study, efficient chicken feather-degrading Streptomyces bacteria were isolated from honeybee samples. Co-cultivation of these bacteria showed an increase in antibiotic production and metabolic wealth. The production of specialized metabolites was enhanced in co-culture conditions, leading to improved antimicrobial activity against Staphylococcus aureus.
Article
Chemistry, Multidisciplinary
Laura Vargas-Estrada, Edwin G. Hoyos, Lara Mendez, P. J. Sebastian, Raul Munoz
Summary: The addition of carbon-coated zero-valent iron nanoparticles at a concentration of 70 mg L-1 enhanced photosynthetic activity and increased biomass concentration. It also improved CO2 removal and increased the methane concentration in the upgraded biogas. However, the higher biomass productivity led to a depletion of the inorganic carbon concentration and a reduction in buffer capacity, requiring further optimization of operational conditions.
SUSTAINABLE CHEMISTRY AND PHARMACY
(2023)
Article
Chemistry, Multidisciplinary
Javier Gonzalez-Martin, Sara Cantera, Raquel Lebrero, Raul Munoz
Summary: Biotechnologies, particularly bioactive coatings, are effective in reducing indoor air pollutants by allowing direct contact between microorganisms and gas pollutants. The removal efficiency of toluene, alpha-pinene, and n-hexane was assessed in three bioreactors with different inoculum and operational conditions. Toluene and alpha-pinene removals >90% were achieved in two bioreactors, while hexane showed low removal efficiency due to mass transfer limitations.
SUSTAINABLE CHEMISTRY AND PHARMACY
(2023)
Article
Agricultural Engineering
Claudia Amabile, Teresa Abate, Simeone Chianese, Dino Musmarra, Raul Munoz
Summary: This study assessed the potential of Methylocystis hirsuta to use methane and volatile fatty acids mixtures for triggering PHBV accumulation. Bioreactors with methane alone confirmed the inability of Methylocystis hirsuta to produce PHBV and achieved a PHB yield of 71.2 ± 7 g m- 3d-1. The inclusion of pure valeric acid and different synthetic mixtures influenced the synthesis of PHBV, suggesting that the composition of the mixtures can be adjusted during the anaerobic digestion process.
BIORESOURCE TECHNOLOGY
(2023)
Article
Engineering, Environmental
Maria del Rosario Rodero, Alessandro A. Carmona-Martinez, Cristina Martinez-Fraile, Raquel Herrero-Lobo, Elisa Rodriguez, Pedro A. Garcia-Encina, Mar Pena, Raul Munoz
Summary: This study assessed the potential of producing ectoine from biogas under different reactor conditions and found that a stand-alone reactor demonstrated the best performance in ectoine accumulation and CH4 degradation.
Article
Engineering, Environmental
Andres F. Torres-Franco, Deborah Leroy-Freitas, Cristina Martinez-Fraile, Elisa Rodriguez, Pedro A. Garcia-Encina, Raul Munoz
Summary: Anaerobic and microalgae-based technologies have emerged as sustainable alternatives for municipal wastewater treatment. However, the presence of viruses in the treated wastewater is a major concern for reuse applications. This study assessed the ability of these technologies to reduce viruses during secondary wastewater treatment. The results showed that all technologies were effective in reducing the concentration of viruses, with microalgae-based treatment exhibiting the highest potential for reducing the disinfection requirements of treated wastewater.
Article
Environmental Sciences
Sara Cantera, Elisa Rodriguez, Nicolas Santaella Vecchini, Juan Carlos Lopez, Pedro A. Garcia-Encina, Diana Z. Sousa, Raul Munoz
Summary: This study investigated the survival and metabolic mechanisms of methane oxidizing bacteria (MOB) under low methane concentrations. The research found that the activity and energy production of methane oxidation were not lost during starvation periods, and poly-hydroxyalkanoate and nitrification metabolism played important roles in maintaining cell viability of MOB. The genus Methylocystis emerged as a key MOB in environments with diluted and intermittent methane emissions.
ENVIRONMENTAL RESEARCH
(2023)
