Article
Engineering, Environmental
Nerea Uri-Carreno, Per H. Nielsen, Krist V. Gernaey, Qian Wang, Ulla Gro Nielsen, Marta Nierychlo, Susan H. Hansen, Lisette Thomsen, Xavier Flores-Alsina
Summary: Membrane-Aerated Biofilm Reactors (MABRs) are an effective alternative for wastewater treatment plants (WWTP) with enhanced nitrogen removal capacity and reduced energy consumption. This study demonstrates the impact of oxidation-reduction potential (ORP) on the performance of MABRs, showing that low ORP conditions can hinder nitrification. By increasing ORP and replacing/cleaning membranes, nitrification rates and the abundance of nitrifying organisms were significantly improved. The study also suggests that low ORP conditions promote the reduction of iron and sulfur compounds, leading to deposition in the biofilm and inhibiting nitrifiers growth.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Genetics & Heredity
Shougang Wang, Xiaoyan Su, Han Cui, Meng Wang, Xiaoli Hu, Wei Ding, Weipeng Zhang
Summary: This study compared the ability of full-length 16S rRNA gene sequencing technique on the PacBio platform and partial 16S rRNA gene sequencing on the traditional Illumina platform to identify microbes in marine biofilms. The results showed that marine biofilms had higher microbial species richness compared to seawater communities, and PacBio sequencing detected more specific species unique to biofilms. The enrichment of specific species in biofilms, such as Vibrio, Arcobacter, Photobacterium, Pseudoalteromonas, and Thalassomonas, confirms previous understanding of species adapted to a surface-associated lifestyle.
Article
Ecology
Ema Kostesic, Maja Mitrovic, Katarina Kajan, Tamara Markovic, Bela Hausmann, Sandi Orlic, Petra Pjevac
Summary: Hot spring biofilms are stable and complex microbial structures, composed of microorganisms adapted to extreme temperatures and fluctuating geochemical conditions. In Croatia, poorly investigated geothermal springs host biofilm communities dominated by Cyanobacteria. Temperature is the strongest driver of biofilm microbial community composition. Besides Cyanobacteria, Chloroflexota, Gammaproteobacteria, and Bacteroidota are the main groups found in the biofilms. Microbial activity in the biofilm communities is surprisingly similar, regardless of their composition and hot spring geochemistry.
Article
Engineering, Environmental
Didrik Villard, Inger Andrea Nesbo Goa, Inga Leena Angell, Sondre Eikaas, Torgeir Saltnes, Wenche Johansen, Knut Rudi
Summary: Many wastewater treatment plants rely on microorganisms in biofilms, but our understanding of the establishment of these biofilms, particularly those involved in enhanced biological phosphorus removal (EBPR), is limited. The Hias process combines MBBR technology with physical transfer of biofilm-carriers to solve the challenge of achieving alternating oxic and anaerobic conditions for phosphorus uptake. Through biofilm fractionation and temporal analyses, we discovered a new model for biofilm growth in the Hias process, but the mechanisms for phosphorus removal are still largely unknown.
WATER SCIENCE AND TECHNOLOGY
(2023)
Article
Microbiology
Er-Meng Yu, Zhen-Chi Li, Zhi-Fei Li, Guang-Jun Wang, Yun Xia, Kai Zhang, Jing-Jing Tian, Wang-Bao Gong, Jun Xie
Summary: The addition of biofilm substrata with external carbon effectively controlled total ammonia nitrogen in aquaculture, improving fish growth. Bacterial compositions were significantly different between the biofilm-substrata-added and biofilm-substrata-free systems, with Planctomycetes playing a key role in ammonia nitrogen control. This study demonstrated that biofilm substrata addition and an external carbon source can enhance fish growth and improve aquaculture environments by shaping a unique bacterial community.
Article
Engineering, Environmental
Wang Qiongjie, Zhang Yong, Zhang Yangyang, Liu Zhouqi, Wang Jinxiaoxue, Chen Huijuan
Summary: This study found that biofilm can enhance the adsorption capacity of microplastics to copper and lead, while the influence of UV radiation is minimal. According to modeling analysis, adsorption on V-PS is dominated by intra-particle diffusion, while the adsorption rate on UV-PS and Bio-PS is mainly controlled by binding diffusion. Bio-PS has the strongest adsorption capacity and the adsorption mechanisms include physical adsorption, chemisorption, and biosorption.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Food Science & Technology
Meera Ongmu Bhutia, Namrata Thapa, Jyoti Prakash Tamang
Summary: The microbiological quality of traditionally preserved fish products from Sikkim, India was assessed in this study, revealing the presence of various potential pathogenic bacteria. Antibiotic susceptibility testing showed that the majority of samples were sensitive to several antibiotics. However, enterotoxins produced by Bacillus cereus and Staphylococcus were detected in some samples, highlighting potential health risks associated with these products.
Article
Microbiology
Limin Wei, Bo Zeng, Siyuan Zhang, Wei Guo, Feng Li, Jiangchao Zhao, Ying Li
Summary: This study compared and analyzed the gut microbiota of wild boar and its offspring using multi-omics technologies. The results showed that the gut microbiota of F4 exhibited host-like dominance with increased abundance of Lactobacillus and Bifidobacterium. Additionally, F4 showed similar metabolic pathways as Duroc. The findings provide reference data for the genetics and evolution of microbiota and microbial-assisted breeding theory.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Food Science & Technology
Paula Fernandez-Gomez, Marcia Oliveira, Jose F. Cobo-Diaz, Montserrat Gonzalez-Raurich, Rodolfo Mugica-Vidal, Fernando Alba-Elias, Miguel Prieto, Avelino Alvarez-Ordonez, Mercedes Lopez
Summary: This study evaluates the anti-biofilm activity of a coating applied with an atmospheric-pressure plasma jet system on stainless steel against multispecies biofilms containing Listeria monocytogenes. The results show that the coating is effective against L. monocytogenes in mono-species biofilms, but its activity is reduced in multispecies biofilms. The disinfection treatments with sodium hypochlorite or peracetic acid effectively control L. monocytogenes growth, with sodium hypochlorite providing stronger control on multispecies biofilms.
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
(2023)
Article
Multidisciplinary Sciences
Ke Zhang, Rongnan Lin, Yujun Chang, Qing Zhou, Zhi Zhang
Summary: 16S-FASAS is a valuable tool for processing and interpreting full-length 16S rRNA gene sequencing results. It includes modules for data quality control, denovo assembly, annotation, and visualization, and has demonstrated excellent performance on mock communities and fecal samples.
Article
Engineering, Chemical
Tamar Jamieson, Sergio Balzano, Charlotte Le Lan, Tim Kildea, Amanda V. Ellis, Melissa H. Brown, Sophie C. Leterme
Summary: Water scarcity affects 40% of the global population, with an estimated 700 million people potentially displaced by drought by 2030. SWRO desalination is an effective method to produce freshwater, but biofouling of SWRO membranes can hinder plant efficiency. This study found that the pre-treatment system removed microorganisms from the water, but niche communities could still establish and proliferate due to environmental adaptation.
Article
Immunology
Suat Moi Puah, Sam Pei Fong, Boon Pin Kee, S. D. Puthucheary, Kek Heng Chua
Summary: This study re-evaluated 30 archived Flavobacterium meningosepticum isolates and identified them as either E. anophelis or E. miricola using 16S rRNA gene sequencing, ERIC-PCR, and biofilm formation assay. The results showed that E. anophelis had a higher ability to form biofilm compared to E. miricola. Additionally, E. anophelis from tracheal secretions were significantly associated with strong biofilm formation. This suggests that E. anophelis may play a significant role in the pathogenesis of Elizabethkingia infections.
MICROBIAL PATHOGENESIS
(2022)
Article
Microbiology
Bhumika Shokeen, Elaine Pham, Julia Esfandi, Takeru Kondo, Hiroko Okawa, Ichiro Nishimura, Renate Lux
Summary: The oral cavity contains various ecological niches that affect biofilm formation and composition. Calcium ion supplementation has a significant impact on the formation and composition of oral microbial biofilms, with differences observed between healthy individuals and periodontitis patients. This study highlights the importance of calcium in the intraoral microenvironment for biofilm formation.
Article
Microbiology
Kensuke Watanabe, U. Yanagi, Yoshiki Shiraishi, Kazuhiro Harada, Fumitoshi Ogino, Koichiro Asano
Summary: HVAC systems have a significant impact on indoor air quality, and microbial contamination inside AC units varies across different parts of the system. The AC filter surface provides a history of indoor airborne bacterial contamination, with most of the detected bacteria being Gram-negative species. Various factors influence the bacterial flora inside AC units.
Article
Multidisciplinary Sciences
Krista L. Bonfantine, Stacey M. Trevathan-Tackett, Ty G. Matthews, Ana Neckovic, Han Ming Gan
Summary: High throughput sequencing is being used to improve the efficiency of monitoring diatoms in aquatic ecosystems. This study demonstrated the potential of a standard V4 515F-806RB primer pair in recovering diatom plastid 16S rRNA sequences, and successfully identified diatom operational taxonomic units from freshwater biofilm samples in Australia. The results indicate that existing 16S rRNA amplicon datasets can be used to map diatom distribution, inform phylogeny and ecological health assessments, and have potential applications in ecological and industrial fields.
Review
Microbiology
Hans-Curt Flemming, Eric D. van Hullebusch, Thomas R. Neu, Per H. Nielsen, Thomas Seviour, Paul Stoodley, Jost Wingender, Stefan Wuertz
Summary: In this review, the authors revisit the understanding of the biofilm matrix and discuss the diversity of its components and the novel aspects of their functional interactions. The biofilm matrix plays a crucial role in stabilizing microbial cells and fulfilling various functions. It is dynamic and influenced by physico-chemical and biological interactions as well as environmental conditions.
NATURE REVIEWS MICROBIOLOGY
(2023)
Article
Chemistry, Analytical
Fuxing Kang, Wei Yang, Mengwen Guo, Lars Borregaard Pedersen, Lars Peter Nielsen
Summary: Developing a PH3 microsensor with high selectivity and sensitivity is crucial for monitoring PH3 in aquatic or sedimentary environments. The sensor utilizes an Au-coated Pt working electrode and Pt guard electrode to selectively oxidize PH3, generating a current proportional to its concentration. By eliminating major H2S disruptors, the effects of other gases on the microsensor can be ignored.
ANALYTICAL CHEMISTRY
(2023)
Article
Environmental Sciences
J. M. S. Oliveira, J. S. Poulsen, E. Foresti, J. L. Nielsen
Summary: A multiple stage anaerobic system was proven effective for reductive decolorization of azo dyes in the presence of sulfate. The system achieved significant bulk color removal and organic matter and sulfate reduction in separate reactors. By utilizing amplicon sequencing and correlation analysis, the microbial communities and pathways involved in azo dye removal were identified, with reductive decolorization being mainly associated with hydrogen-producing pathways and the involvement of an azoreductase from Lactococcus lactis. The findings enhance our understanding of the role of different microbial communities in anaerobic treatment of azo dyes and can aid in the design of improved solutions for textile effluent treatment.
Article
Ecology
Mantas Sereika, Francesca Petriglieri, Thomas Bygh Nymann Jensen, Artur Sannikov, Morten Hoppe, Per Halkjaer Nielsen, Ian P. G. Marshall, Andreas Schramm, Mads Albertsen
Summary: Cable bacteria are centimeter-long filamentous bacteria capable of long-distance electron transfer. They are currently classified into two candidate genera: Candidatus Electronema, found in freshwater, and Candidatus Electrothrix, found in saltwater. To address the lack of complete genomic information, researchers performed Nanopore long-read and Illumina short-read shotgun sequencing, resulting in the recovery of multiple cable bacteria genomes. Phylogenomic analysis classified two circular genomes as novel species: Ca. Electronema halotolerans and Ca. Electrothrix laxa. The discovery of Ca. Electronema halotolerans in brackish-water sediment suggests its evolutionary link between marine and freshwater cable bacteria lineages.
Article
Agricultural Engineering
Agnieszka Garlicka, Katarzyna Umiejewska, Per Halkjaer Nielsen, Adam Muszynski
Summary: The aim of this project was to increase methane production by combining feedstock pretreatment and co-digestion of maize silage with thickened excess sludge. Results showed that pretreatment of sludge alone increased methane production from 0.192 Nml/gVS (sludge + maize silage) to 0.220 Nml/gVS (pretreated sludge + maize silage). However, the energy balance indicated that the additional energy generated was not enough to cover the energy expenditure for the mechanical pretreatment. 16S rRNA gene amplicon sequencing revealed the composition of the microbial community, with Chloroflexi, Bacteroidota, Firmicutes, Proteobacteria, and Actinobacteriota being the most abundant bacteria phyla.
BIORESOURCE TECHNOLOGY
(2023)
Article
Microbiology
Linda Hink, Anja Holzinger, Tobias Sandfeld, Alfons R. Weig, Andreas Schramm, Heike Feldhaar, Marcus A. Horn
Summary: Microplastic (MP) is a burden to the environment and enters food webs through ingestion by macrofauna like isopods in terrestrial ecosystems. This study examines the effects of biodegradable (polylactic acid [PLA]) and non-biodegradable (polyethylene terephthalate [PET]; polystyrene [PS]) MPs on the isopod host and its gut microbiota. The findings suggest that PLA stimulates microbial activity and hydrogen emission from the isopod guts, while PET and PS have inhibitory effects on gut fermentation. This study highlights the potential of MP to affect terrestrial food webs.
ENVIRONMENTAL MICROBIOLOGY
(2023)
Article
Biochemical Research Methods
Jan Struckmann Poulsen, Jeppe Lund Nielsen
Summary: Synthetic plastics, such as PET, are widely used but pose a major threat due to their environmental persistence. The bacterium I. sakaiensis has been discovered to solely thrive on degrading PET films and its monomers. By analyzing protein expression, it was revealed that PET and its monomers induce the MHETase and affect two major pathways: the TCA cycle and the beta-oxidation pathway. The increased expression of proteins involved in these pathways suggests their importance in the degradation process.
JOURNAL OF PROTEOMICS
(2023)
Article
Multidisciplinary Sciences
Laura Eme, Daniel Tamarit, Eva F. Caceres, Courtney W. Stairs, Valerie De Anda, Max E. Schoen, Kiley W. Seitz, Nina Dombrowski, William H. Lewis, Felix Homa, Jimmy H. Saw, Jonathan Lombard, Takuro Nunoura, Wen-Jun Li, Zheng-Shuang Hua, Lin-Xing Chen, Jillian F. Banfield, Emily St John, Anna-Louise Reysenbach, Matthew B. Stott, Andreas Schramm, Kasper U. Kjeldsen, Andreas P. Teske, Brett J. Baker, Thijs J. G. Ettema
Summary: Through analysis of an expanded genomic sampling of Asgard archaea, this study reveals that eukaryotes are placed within Asgard archaea as a well-nested clade and a sister lineage to Hodarchaeales. The study also shows that genome evolution in Asgard archaea involved more gene duplication and fewer gene loss events compared to other archaea.
Article
Engineering, Environmental
Martin Hjorth Andersen, Lisette Thomsen, Mikkel Stokholm-Bjerregaard, Susan Hove Hansen, Mads Albertsen, Per Halkjaer Nielsen, Soren Eriksen
Summary: The partial nitritation/anammox process is a popular approach for removing nitrogen from sidestreams, but it requires extensive surveillance and monitoring due to its sensitivity to disturbances. In this study, we utilized online sensor data and Nanopore DNA sequencing to monitor the microbial community and detect system disturbances in two full-scale deammonification reactors over a year. DNA surveillance revealed unexpected variations in anammox bacteria, and the composition and dynamics of the surrounding community indicated causes for occasional process disturbances. Monitoring the ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) could potentially optimize reactor operation. The use of frequent DNA sequencing was found to be an important supplement to online sensor data for process surveillance and control.
Article
Multidisciplinary Sciences
Jesper J. Bjerg, Jamie J. M. Lustermans, Ian P. G. Marshall, Anna J. Mueller, Signe Brokjaer, Casper A. Thorup, Paula Tataru, Markus Schmid, Michael Wagner, Lars Peter Nielsen, Andreas Schramm
Summary: Cable bacteria are filamentous microbes that conduct electrons via internal wires and couple sulfide oxidation between sediment layers. Other bacteria swarm around the anoxic part of oxygen-respiring cable bacteria and seem to transfer electrons to cable bacteria via soluble metabolites. This association and interaction with diverse partners may explain how oxygen from cable bacteria affects microbial communities and processes in anoxic environments.
NATURE COMMUNICATIONS
(2023)
Article
Agricultural Engineering
Jan Struckmann Poulsen, Alba Trueba-Santiso, Juan M. Lema, Simon Gregersen Echers, Reinhard Wimmer, Jeppe Lund Nielsen
Summary: In this study, the biodegradability of PBAT monomers in thermophilic conditions was investigated using anaerobic digester sludge. 13C-labelled monomers and proteogenomics were used to track labelled carbon and identify the microorganisms involved in the process. Bacteroides, Ichthyobacterium, and Methanosarcina were found to be directly involved in the metabolization of at least one monomer.
BIORESOURCE TECHNOLOGY
(2023)
Article
Dentistry, Oral Surgery & Medicine
M. F. Kristensen, M. B. Lund, A. Schramm, E. Frandsen Lau, S. Schlafer
Summary: This study comprehensively analyzed the effect of whole saliva flow on microscale pH in dental biofilms using pH ratiometry. The results showed the presence of steep pH gradients and a positive correlation between pH drops and biofilm thickness. Stimulated saliva flow increased biofilm pH but did not balance the vertical and horizontal pH gradients. Dental biofilms with different pH responses had significantly different bacterial community composition.
JOURNAL OF DENTAL RESEARCH
(2023)
Article
Plant Sciences
Jan Struckmann Poulsen, Christina Kjaerager Nielsen, Nina Ahrendt Pedersen, Reinhard Wimmer, Teis Esben Sondergaard, Nadieh de Jonge, Jeppe Lund Nielsen
Summary: Proteomics analysis revealed that combining methicillin with three cannabinoid compounds could decrease energy production and increase the production of penicillin-binding protein 2 (PBP2), which is associated with antibiotic resistance in MRSA.
JOURNAL OF NATURAL PRODUCTS
(2023)
Article
Chemistry, Analytical
Fuxing Kang, Wei Yang, Mengwen Guo, Lars Borregaard Pedersen, Lars Peter Nielsen
Summary: Monitoring PH3 flux at the Earth's surface-atmosphere interface is a challenging task. A new amperometric PH3 microsensor with high selectivity and sensitivity is developed for in situ detection in aquatic or sedimentary environments. The sensor uses a Au-coated Pt working electrode and a Pt guard electrode, and employs a two-layer silicone membrane to selectively oxidize PH3 into H3PO4, producing a current proportional to the PH3 concentration (>2 nmol center dot L-1). The sensor is designed to eliminate interferences from H2S and other gases, making it suitable for environmental monitoring. A sedimentary profile example demonstrates the presence of high PH3 accumulations 13 mm below the sediment surface.
ANALYTICAL CHEMISTRY
(2023)
Article
Microbiology
Jeanine S. Geelhoed, Casper A. Thorup, Jesper J. Bjerg, Lars Schreiber, Lars Peter Nielsen, Andreas Schramm, Filip J. R. Meysman, Ian P. G. Marshall
Summary: In this study, we identified a novel species of marine cable bacteria with a large diameter, named Candidatus Electrothrix gigas. The genomes of this species contain a gene encoding a novel actin-like protein (Bbp) that is also found in other giant bacteria. This suggests that there may be a genetic basis for large cell size. The Bbp protein may have a structural role in the cell or potentially facilitate intracellular transport.
MICROBIOLOGY SPECTRUM
(2023)
