Towards a predictive framework for microbial management in drinking water systems

QR Microbiology;TA Engineering (General). Civil engineering (General);TD Environmental technology. Sanitary engineering

Bautista de los Santos, Quyen Melina ; Engineering and Physical Sciences Research Council (EPSRC) ; Pinto, Ameet

University:University of Glasgow

Department:School of Engineering

关键词: Drinking water, DNA sequencing, microbial ecology.;   

Others  :  http://theses.gla.ac.uk/8261/1/2017BautistadelosSantosphd.pdf

来源: University of Glasgow

【 摘 要 】

The application of DNA sequencing-based approaches to drinking water microbial ecology has revealed the presence of an abundant and diverse microbiome; therefore, the possibility of harnessing drinking water (DW) microbial communities is an attractive prospect in order to address some of the current and emerging challenges in the sector. Moreover, these multiple challenges suggest that a shift in the DW sector, from a “reactive and sanctioning” paradigm to a “due diligence/proactive” based approach may be the key in identifying potentially adverse events. My research project has focused on the characterization of the microbial ecology of full-scale DW systems using DNA sequencing-based approaches, with the aim of exploring how the obtained insights could be applied into a predictive/proactive microbial management approach. To achieve this aim, I have focused my efforts on sampling multiple full-scale DW systems in order to elucidate the impacts of: (i) methodological variation and (ii) system properties on DW microbial communities, using a combination of bioinformatics, molecular biology, microbial ecology and multivariate statistical analyses.Regarding methodological variation, I have elucidated the impacts of sample replication, PCR replication, sample volume and sampling flow rate on the structure and membership of DW microbial communities. This was the first time that methodological variation was explored in the DW context, and the first time that multi-level replication has been tested and applied in DW molecular microbial ecology. Moreover, my findings have direct implications for the design of future sampling campaigns. Regarding system properties, I have shown that microbial communities in DW distribution systems (DWDSs) undergo diurnal variation, and therefore are linked to water use patters/hydraulics in the systems. I have also shown that sampling locations in the same distribution system are similar, with OTUs found across sampling locations at different relative abundance and detection frequency levels. An assessment of the impact of source water type and treatment processes showed that disinfection is a key treatment step for community composition and functional potential, and that several genes related to protection against chlorine/oxygen species are overabundant in chlorinated and chloraminated systems. Looking to the future, I believe that the application of a “toolbox” of techniques is key in shifting towards a proactive approach in DW management, that multidisciplinary synergies hold the possibility of changing the way in which DW systems have been studied and managed for over 100 years.