McIlroy, S.J., Kirkegaard, R.H., McIlroy, B., Nierychlo, M., Kristensen, J.M., Karst, S.M., Albertsen, M., Nielsen, P.H., 2017. MiDAS 2.0: an ecosystem-specific taxonomy and online database for the organisms of wastewater treatment systems expanded for anaerobic digester groups. Database 2017. doi:10.1093/database/bax016

McIlroy, S.J., Saunders, A.M., Albertsen, M., Nierychlo, M., McIlroy, B., Hansen, A.A., Karst, S.M., Nielsen, J.L. and Nielsen, P.H. (2015) MiDAS: the field guide to the microbes of activated sludge. Database, Vol. 2015, Article ID bav062; doi:10.1093/database/bav062.

Read more about our conceptual model of the activated sludge ecosystem:

Saunders A. M., Albertsen M., Vollertsen J., Nielsen P.H. (2016) The activated sludge ecosystem contains a core community of abundant organisms. ISME Journal, 10: 11-20. doi: 10.1038/ismej.2015.117.

Albertsen M., Karst S.M., Ziegler A.S., Kirkegaard R.H., Nielsen P.H. (2015) Back to basics – the influence of DNA extraction and primer choice on phylogenetic analysis in activated sludge communities. PLOS ONE, doi: 10.1371/journal.pone.0132783.

Nielsen, P.H., Saunders, A.M., Hansen, A.A., Larsen, P., & Nielsen, J.L. (2012). Microbial communities involved in enhanced biological phosphorus removal from wastewater - a model system in environmental biotechnology. Current Opinion in Biotechnology, 23(3), 452–459.

Nielsen, P.H., Mielczarek, A.T., Kragelund, C., Nielsen, J.L., Saunders, A.M., Kong, Y., Hansen, A.A., Vollertsen J. (2010). A conceptual ecosystem model of microbial communities in enhanced biological phosphorus removal plants. Water Research, 44, 5070–5088.


Examples of articles citing and using MiDAS:

Ziegler, AS, SJ McIlroy, P Larsen, M Albertsen, AA Hansen, N Heinen, and PH Nielsen (2016): Dynamics of the fouling layer microbial community in a membrane bioreactor. PloSONE. DOI: 10.1371/journal.pone.0158811.

Law, Y, RH Kirkegaard, AA Cokro, X Liu, K Arumugam, C Xie, M Stokholm-Bjerregaard, DI Drautz-Moses, PH Nielsen, S Wuertz, RBH Williams (2016): Integrative microbial community analysis reveals full-scale enhanced biological phosphorus removal under tropical conditions. Scientific Rep. 6, 25719. doi:10.1038/srep25719.

Cokro, AA, Y Law, RBH Williams, Y Cao, PH Nielsen, S Wuertz (2017): Non-denitrifying polyphosphate accumulating organisms obviate requirement for anaerobic condition. Water Research 111, 393–403. doi:10.1016/j.watres.2017.01.006

Szabó, E., R Liébana, M Hermansson, O Modin, F Persson, and B-M Wilén (2017): Microbial Population Dynamics and Ecosystem Functions of Anoxic/Aerobic Granular Sludge in Sequencing Batch Reactors Operated at Different Organic Loading Rates. Frontiers in Microbiology 8. doi:10.3389/fmicb.2017.00770

Stokholm-Bjerregaard, M., McIlroy, S.J., Nierychlo, M., Karst, S.M., Albertsen, M., Nielsen, P.H., (2017): A Critical Assessment of the Microorganisms Proposed to be Important to Enhanced Biological Phosphorus Removal in Full-Scale Wastewater Treatment Systems. Front. Microbiol. 8.

Gonzalez-Martinez, A., Sihvonen, M., Muñoz-Palazon, B., Rodriguez-Sanchez, A., Mikola, A., Vahala, R., (2018). Microbial ecology of full-scale wastewater treatment systems in the Polar Arctic Circle: Archaea , Bacteria and Fungi. Scientific Reports 8, 2208.

Fang, D., Zhao, G., Xu, X., Zhang, Q., Shen, Q., Fang, Z., Huang, L., Ji, F., (2018): Microbial community structures and functions of wastewater treatment systems in plateau and cold regions. Bioresource Technology 249, 684–693.

to see full citation list, please click here (McIlroy et al., 2015) and here (McIlroy et al., 2017).



DNA extraction and primer selection for Activated Sludge

MEWE 2013 workshop by Søren M. Karst (Aalborg University, Denmark).


The importance of a curated 16S database

MEWE 2013 workshop by Aaron M. Saunders (Aalborg University, Denmark).

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