Microbiome analysis of aquatic microbial communities of the urban water systems in Bandar Sunway, Malaysia

In this study, water from nine sites from the lake and river in Bandar Sunway was characterized (from three independent sampling periods), and paired with microbial analysis to reflect the extent of the impact of urbanization on water systems in Bandar Sunway. Microbial communities were characterized using Illumina MiSeq with amplifications of V3-V4 and V9 hyper-variable region of 16S and 18S rRNA genes, respectively. The 16S rRNA analysis revealed Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes as the dominant prokaryotic phyla, while 18S rRNA analysis revealed that eukaryotic communities are predominantly of the SAR clade and Opisthokonta. The abundance of Pseudomonas and Flavobacterium in all sites suggested possible presence of pathogen in the urban water systems. This correlates to the most probable number (MPN) values of more than 1600 per 100 mL derived from all sites. The abundance of Cyanobacteria suggests possible toxic blooming in Kelana Jaya lake. Observations indicated that urbanization may have impacted the microbial communities as transient communities (clinical, waterborne and opportunistic pathogens) may co-exist with common indigenous aquatic communities (Cyanobacteria). The alpha diversity analysis indicated that the core microbial community structure is not affected by the different sampling periods. The beta diversity analysis showed that the overall microbial community is similar between sites. This study suggested that while urbanization in Bandar Sunway may have no significant impact on diversity of microbial communities, the changes to the abundance of microbial phyla are detected along the water systems. This is the first study utilizing 16S and 18S rRNA amplicon sequencing approach to investigate the microbial communities in the urban water system in Bandar Sunway. The results revealed the impact of rapid urbanization activities, which led to the abundance of various microbial communities along the urban water system.