MicrobiAl Metabolism in the Boundary of Oxic-anoxic conditions

PID2020-117340RA // Convocatoria 2020 Proyectos de I+D+i – RTI, Ministerio de Ciencia e Innovación  // PI: Emilio Garcia-Robledo (202.070 €)

Project description

Oxygen levels have been decreasing in the open oceans and coastal environments since the half of the past century. Ocean deoxygenation is considered one of the most important changes occurring in marine ecosystems, being caused by global warming and coastal eutrophication. In the open oceans, Oxygen minimum zones (OMZs), regions in which oxygen is depleted at intermediate depths, have expanded an area equivalent to the European Union. Current estimations of the extension of OMZs, their impact on global biogeochemical cycles and the models to understand and predict future scenarios rely on precise oxygen distribution measurements and quantitative understanding of the oxygen consumption processes producing and maintaining anoxic zones.

The main objective of MAMBO is to study the aerobic microbial metabolism in communities exposed to decreasing oxygen conditions, developing methodologies to measure respiration rates in low activity environments and characterize the kinetics of microbial cultures and natural microbial communities and providing high-resolution measurements of the distribution of oxygen at trace levels in the oceans.

This general objective will be addressed by a sequence of action with increasing levels of complexity:

1. characterizing the respiration at low oxygen levels of relevant marine microorganisms, using a broad diversity of microbial cultures
2. characterizing the oxygen metabolism and respiratory kinetics of marine microbial communities from a variety of marine environments including coastal and oceanic locations, shallow and deep water masses and high and low latitude locations, and
3. describing the oxygen distribution with high-resolution techniques and characterizing the kinetics of respiration in aquatic environments with natural decreasing oxygen conditions such as Pacific OMZs

Project activities:

Related research results:

• Garcia-Robledo, E., Paulmier, A., Borisov, S. M., & Revsbech, N. P. (2021). Sampling in low oxygen aquatic environments: The deviation from anoxic conditions. Limnology & Oceanography: Methods in press. doi:10.1002/lom3.10457
• Trojan, D., Garcia-Robledo, E., Meier, D. V., Hausmann, B., Revsbech, N. P., Eichorst, S. A., & Woebken, D. (2021). Microaerobic Lifestyle at Nanomolar O2 Concentrations Mediated by Low-Affinity Terminal Oxidases in Abundant Soil Bacteria. mSystems, 0(0), e0025021. doi:10.1128/mSystems.00250-21
• Sun, X., Frey, C., Garcia-Robledo, E., Jayakumar, A., & Ward, B. B. (2021). Microbial niche differentiation explains nitrite oxidation in marine oxygen minimum zones. The ISME journal, 15(5), 1317-1329. doi:10.1038/s41396-020-00852-3
• Capet, A., Cook, P., Garcia-Robledo, E., Hoogakker, B., Paulmier, A., Rabouille, C., & Vaquer-Sunyer, R. (2020). Editorial: Facing Marine Deoxygenation. Frontiers in Marine Science, 7(46). doi:10.3389/fmars.2020.00046
• Gong, X., Garcia-Robledo, E., Lund, M. B., Lehner, P., Borisov, S. M., Klimant, I., . . . Schramm, A. (2018). Gene expression of terminal oxidases in two marine bacterial strains exposed to nanomolar oxygen concentrations. FEMS Microbiol Ecol, 94(7), fiy072-fiy072. doi:10.1093/femsec/fiy072
• Garcia-Robledo, E., Padilla, C. C., Aldunate, M., Stewart, F. J., Ulloa, O., Paulmier, A., . . . Revsbech, N. P. (2017). Cryptic oxygen cycling in anoxic marine zones. Proceedings of the National Academy of Sciences, 114(31), 8319-8324. doi:10.1073/pnas.1619844114