10.1021/es501601w.s001 Robert P. Ellis Robert P. Ellis John I. Spicer John I. Spicer Jonathan J. Byrne Jonathan J. Byrne Ulf Sommer Ulf Sommer Mark R. Viant Mark R. Viant Daniel A. White Daniel A. White Steve Widdicombe Steve Widdicombe <sup>1</sup>H NMR Metabolomics Reveals Contrasting Response by Male and Female Mussels Exposed to Reduced Seawater pH, Increased Temperature, and a Pathogen American Chemical Society 2014 1 H NMR spectroscopy Female Mussels Exposed seawater pH 1 H NMR Metabolomics Reduced Seawater pH marine stress response impacting OA organism challenge 2014-06-17 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/_sup_1_sup_H_NMR_Metabolomics_Reveals_Contrasting_Response_by_Male_and_Female_Mussels_Exposed_to_Reduced_Seawater_pH_Increased_Temperature_and_a_Pathogen/2282122 Human activities are fundamentally altering the chemistry of the world’s oceans. Ocean acidification (OA) is occurring against a background of warming and an increasing occurrence of disease outbreaks, posing a significant threat to marine organisms, communities, and ecosystems. In the current study, <sup>1</sup>H NMR spectroscopy was used to investigate the response of the blue mussel, Mytilus edulis, to a 90-day exposure to reduced seawater pH and increased temperature, followed by a subsequent pathogenic challenge. Analysis of the metabolome revealed significant differences between male and female organisms. Furthermore, males and females are shown to respond differently to environmental stress. While males were significantly affected by reduced seawater pH, increased temperature, and a bacterial challenge, it was only a reduction in seawater pH that impacted females. Despite impacting males and females differently, stressors seem to act via a generalized stress response impacting both energy metabolism and osmotic balance in both sexes. This study therefore has important implications for the interpretation of metabolomic data in mussels, as well as the impact of environmental stress in marine invertebrates in general.