The role of bacteriophages in an aerobic biogranulation system

Abstract

Relative to conventional activated sludge, aerobic granular sludge systems (AGS) allows for the efficient removal of nutrients and toxins with a smaller footprint. Viral metagenomics and metatranscriptomics studies conducted on AGS systems previously, suggest that inoviridae play a supportive role in the development and maintenance of granules. The aim of this thesis is to investigate the role of bacteriophages in an AGS system, to create a better understanding of its developmental process. Preliminary data from this study has also revealed that there was a relatively higher expression of filamentous phage in the AGS system in a sequencing batch reactor (SBR) as compared to a floccular system from a water reclamation plant. A method known was viral tagging was adopted to further improve the understanding of interactions between phage and host. However, it was found that the original protocol, which involves heat treatment, was not suitable for the studying of the phage community in our systems. Therefore modifications will be made to the protocol in future studies to exclude this treatment. The filtration process for the separation of bacteriophage from the AGS system was also optimized and automated to allow for more efficient and less laborious purification procedure.