Coupled virus - bacteria interactions and ecosystem function in an engineered microbial system

Brown, M.R., Baptista, J.C., Lunn, M., Swan, D.L., Smith, S.J., Davenport, R.J., Allen, B.D., Sloan, W.T. and Curtis, T.P. (2019) Coupled virus - bacteria interactions and ecosystem function in an engineered microbial system. Water Research, 152, pp. 264-273. (doi: 10.1016/j.watres.2019.01.003) (PMID:30682570)

Abstract

Viruses are thought to control bacterial abundance, affect community composition and influence ecosystem function in natural environments. Yet their dynamics have seldom been studied in engineered systems, or indeed in any system, for long periods of time. We measured virus abundance in a full-scale activated sludge plant every week for two years. Total bacteria and ammonia oxidising bacteria (AOB) abundances, bacterial community profiles, and a suite of environmental and operational parameters were also monitored. Mixed liquor virus abundance fluctuated over an order of magnitude (3.18 × 108 – 3.41 × 109 virus’s mL-1) and that variation was statistically significantly associated with total bacterial and AOB abundance, community composition, and effluent concentrations of COD and NH4+- N and thus system function. This suggests viruses play a far more important role in the dynamics of activated sludge systems than previously realised and could be one of the key factors controlling bacterial abundance, community structure and functional stability and may cause reactors to fail. These finding are based on statistical associations, not mechanistic models. Nevertheless, viral associations with abiotic factors, such as pH, make physical sense giving credence to these findings and highlighting the role that physical factors play in virus ecology. Further work is needed to identify and quantify specific bacteriophage and their hosts to enable us to develop mechanistic models of the ecology of viruses in wastewater treatment systems. However, since we have shown that viruses can be related to effluent quality and virus quantification is simple and cheap, practitioners would probably benefit from quantifying viruses now.

• Item Type: Articles
• Additional Information: This work was carried out as part of a Frontiers in Engineering research project (NUFEB, http://research.ncl.ac.uk/nufeb/) awarded and funded by the Engineering and Physical Sciences Research Council (EP/H012133/1).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sloan, Professor William
• Authors: Brown, M.R., Baptista, J.C., Lunn, M., Swan, D.L., Smith, S.J., Davenport, R.J., Allen, B.D., Sloan, W.T., and Curtis, T.P.
• College/School: College of Science and Engineering > School of Engineering > Infrastructure and Environment
• Journal Name: Water Research
• Publisher: Elsevier
• ISSN: 0043-1354
• ISSN (Online): 1879-2448
• Published Online: 11 January 2019
• Copyright Holders: Copyright © 2019 The Authors
• First Published: First published in Water Research 152: 264-273
• Publisher Policy: Reproduced under a Creative Commons License