Eukaryotic phytoplankton community composition in the COAST (Gulf of Mexico, COASTal water mesocosms amended with coastal microbial concentrate) mesocosm as identified by 18S sequence from RNA-seq whole transcriptome sequencing for four treatments (control, WAF, CEWAF, dilute CEWAF)

A mesocosm experiment was conducted October 2015 (COAST, Mesocosm 2) using coastal water collected near Galveston Bay, Texas. Four mesocosm treatments were prepared in triplicate for this study: (1) Control (seawater only); (2) WAF (oil + seawater); (3) Chemically-enhanced WAF (CE-WAF; oil + Corexit + seawater); (4) Diluted CE-WAF (1:10 dilution). Initial mesocosm volumes were 79L. Prior to experiment initiation, phytoplankton were collected from coastal Galveston, TX waters and added to each tank to stimulate interactions between phytoplankton, oil, and Corexit. One sample was taken from all four treatments, three replicate mesocosms each, at time 72 h in clean, opaque Nalgene bottles with PTFE-lined diaphragm pumps. RNA was extracted from filtered water samples and sequenced using Illumina HiSeq. The sequences were deposited at the NCBI short read archive, SRA bioproject code PRJNA489497; https://www.ncbi.nlm.nih.gov/bioproject/PRJNA489497