Quantification of the coupled dynamics of marine microbes and reactive oxygen species in laboratory batch culture experiments

impacts on microbial community composition. IMPORTANCE: Hydrogen peroxide produced naturally in the surface ocean is toxic to many abundant microbes that perform important ecosystem services such as carbon fixation. Much of the naturally occurring hydrogen peroxide produced in the surface ocean is detoxified by "helper" organisms. The healthy function of microbial communities may therefore depend upon the presence of different helpers. Mathematical models provide an important means to evaluate the impacts of hydrogen peroxide on ecosystem function. This study introduces a framework to evaluate the sensitivity of diverse microbes to hydrogen peroxide, in a manner that is amenable for inclusion in ecosystem models. It lays a foundation for future efforts to evaluate the impact of hydrogen peroxide on ecosystem function and microbial community composition.