Metagenomics analysis of bacterial communities in the periphytic biofilms from floating fish cages and their relationship with water physicochemical parameters

In this study, we report the presence of bacterial community in terms of abundance and taxonomic biodiversity from periphytic biofilm samples attached to the surface of floating fish cage components in the Pahang River and their relationship with water physicochemical parameters. Periphytic biofilm samples were collected from five sites located in the different districts alongside the Pahang River. Water physicochemical parameters assessment was also conducted simultaneously during the sampling process. Bacterial deoxyribonucleic acid (DNA) was then extracted from periphytic biofilm samples and sequenced on NovaSEQ6000 by Illumina Next Generation Sequencing (NGS) to construct metagenomics libraries. The results indicated the predominant phyla were Cyanobacteria, which accounted for more than half of the total bacteria detected, followed by Proteobacteria, Planctomycetota and Actinobacteriota. At the class level, the top five most detected classes were Cyanobacteria, Alphaproteobacteria, Gammaproteobacteria, Actinomycetia and Planctomycetes. Statistical analysis discovered a significant correlation between the bacterial abundance and distribution with the water physicochemical parameters. This study is the first report of bacterial abundance and its relationship with water physicochemical parameters in the Pahang River through metagenomic analysis.