Editorial: Extracellular Enzymes in Aquatic Environments: Exploring the Link Between Genomic Potential and Biogeochemical Consequences

Abstract

Microbes drive the Earth's biogeochemical cycles, exerting profound control over the global cycling of carbon and other elements (Falkowski et al., 2008). In aquatic systems, the importance of microbial extracellular enzymes to the mobilization, transformation, and turnover of organic and inorganic compounds in aquatic environments has been proved since the 80's (Hoppe, 1983; Chróst, 1989) and was summarized in the book “Microbial enzymes in aquatic environments” (Chróst, 1991). Since then, the field has advanced considerably, with new observations, assay methods, and molecular-level studies (Arnosti et al., 2014) and the measurement of extracellular enzyme activities has become standard in many labs. We now have rates of enzymatic activities in a wide variety of freshwater and marine environments, from polar to tropical and from surface to deep ocean, and from isolates obtained even from extreme environments. Additionally, in recent years measurement of enzyme activities has become an important tool to assess the impact of anthropogenic changes on microbial communities and biogeochemical cycles, such as in the events of oil spills, acidification, or global warming (e.g., Piontek et al., 2010; Sala et al., 2016; Ziervogel et al., 2016; Freixa et al., 2017)