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



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).

The online MiDAS field guide is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.


The MiDAS taxonomy is a manual curation of the Silva database and is redistributed for non-commercial use only.


Citing MiDAS: McIlroy S.J., Saunders A.M., Albertsen M., Nierychlo M., McIlroy B., Hansen A.A., Karst S.M., Nielsen J.L., Nielsen P.H. (2015) MiDAS: the field guide to the microbes of activated sludge. Database, Vol. 2015

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