Aquasim model for Biofilm Modelling chapter (Chapter 17 by Eberhard Morgenroth)
A new method to treat fracture fluids in situ.
Log removal values for phages, chemical disinfectant, or combined treatment on surface-attached Pseudomonas aeruginosa.
Biofilms serve essential ecosystem functions and are used in different technical applications. Studies from stream ecology and waste water treatment have shown that biofilm functionality depends to a great extent on community structure. Here we present a fast and easy-to-use method for individual cell-based analysis of stream biofilms, based on stain-free flow cytometry and visualization of the high-dimensional data by viSNE. The method allows the combined assessment of community structure, decay of phototrophic organisms and presence of abiotic particles. In laboratory experiments, it allows quantification of cellular decay and detection of survival of larger cells after temperature stress, while in the field it enables detection of community structure changes that correlate with known environmental drivers (flow conditions, dissolved organic carbonDOC, calcium) and detection of microplastic contamination. The method can potentially be applied to other biofilm types, e.g. for inferring community structure for environmental and industrial research and monitoring.
Autotrophic nitrogen removal by anaerobic ammonium oxidizing (anammox) bacteria is an energy-efficient nitrogen removal process in wastewater treatment. However, full-scale deployment under mainstream conditions remains challenging for practitioners due to the high stress susceptibility of anammox bacteria towards fluctuations in dissolved oxygen (DO) and temperature. Here, we investigated the response of microbial biofilms with verified anammox activity to DO shocks under 20 °C and 14 °C. While pulse disturbances of 0.3 mg L−1 DO prompted only moderate declines in the NH4+ removal rates, 1.0 mg L−1 DO led to complete but reversible inhibition of the NH4+ removal activity in all reactors. Genome-centric metagenomics and metatranscriptomics were used to investigate the stress response on various biological levels. We show that temperature regime and strength of DO perturbations induced divergent responses from the process level down to the transcriptional profile of individual taxa. Community-wide gene expression differed significantly depending on the temperature regime in all reactors, and we found a noticeable impact of DO disturbances on genes involved in transcription, translation, replication and posttranslational modification at 20 °C but not 14 °C. Genome-centric analysis revealed that different anammox species and other key biofilm taxa differed in their transcriptional responses to distinct temperature regimes and DO disturbances.
This living document will illustrate Standard Operating Procedures (SOPs) for sampling biofilm material from reverse osmosis (RO) membrane modules. The SOPs will empower the NAWI research community to apply omics tools (e.g., time-series metagenomic, meta-transcriptomic, metaproteomic and metabolomic workflows) to fundamentally understand biofilm formation with unprecedented resolution (e.g., the transition from innocuous to detrimental biofilm) and mitigate biofouling in water treatment and distribution systems.
SUMO model for Biofilm Modelling chapter in IWA Biological Wastewater Treatment: 2nd edition.