title: Comparative Microbial Metagenomic Analysis of Drinking Water Plants and Wastewater Treatment Plants in Istanbul
design: Comparative Microbial Metagenomic Analysis of Drinking Water Plants and Wastewater Treatment Plants in Istanbul
library_construction_protocol: There were 52 water samples, 18 from drinking water treatment plants (DWTPs) and 34 from wastewater treatment plants (WWTPs).  We collected raw waters entering DWTP, waters subjected to oxidation after ozonation, raw waters taken from the inlet and outlet points of WWTPs, treated wastewater, and waters recycled through ultraviolet disinfection after treatment in WWTPs. All water samples were filtered through Whatman vacuum filtration. DNA extraction from Whatman filter papers was done using a spin column-based commercial nucleic acid extraction kit (Nucleogene Ltd., Kartal, Istanbul). This step was conducted using an Illumina DNA Prep kit (Illumina, USA, #20060059) and all kits were used according to the manufacturer's protocols. During library preparation, IDT for IlluminaÂ® DNA/RNA UD Indexes Set C (Illumina, USA, #20042666) adapters were used for sample indexing. The library was measured using a Qubit 4 Fluorometer and normalized before sequencing.