Phosphate limitation intensifies negative effects of ocean acidification on globally important nitrogen fixing cyanobacterium. Phosphate limitation intensifies negative effects of ocean acidification on globally important nitrogen fixing cyanobacterium

The filamentous diazotrophic cyanobacteria Trichodesmium spp. supply fixed nitrogen (N) to the N-depleted oligotrophic oceans where their growth is often limited by the low availability of phosphorus(P) and/or iron. Previous studies have mostly been focused on the effects of ocean acidification on Trichodesmium under nutrient sufficient or iron-limited conditions. Only a few studies have examined the impacts of ocean acidification on Trichodesmium grown at low P concentrations using non-steady-state batch cultures. Here we cultured Trichodesmium using P-limited continuous cultures (chemostat) to mimic steady-state oceanic low P condition, and used comparative NGS-derived Trichodesmium transcriptome profiling (RNA-seq) analysis to find differentially expressed genes and cellular pathways in response to acidification. Overall design: mRNA profiles of phosphorus limited Trichodesmium cultured at 400 µatm pCO2 (LP_400) and 750 µatm pCO2 (LP_800)