Extreme Environments: Hot

We study the microbial communities forming mats in hot springs. These springs are like hot islands in a colder “ocean” surrounding them. Therefore, they can be used to analyze dispersal of microbial taxa from one to another. We have sampled springs along the cordilleras of Costa Rica and along the Andes in Chile, from El Tatio in the north to San Ignacio del Huinay in the south. We have also collected mat samples in Deception Island, Antarctica. In the future we are planning sampling expeditions in Perú and other countries.

Altogether we have samples at different space scales, from cm to thousands of kilometers, along a latitudinal gradient. This permits analysis of the importance of dispersal limitation for bacteria.

We also analyze metagenomes and metatranscriptomes of the mat communities, assembling genomes of the most important members of the community and determining their role in the ecology of the ecosystem.

Microbial mats at El Tatio (4200 masl, Chile)
  1. Latitudinal distribution of hot spring microbes
  2. Reconstruction of carbon and nitrogen metabolism in microbial mats
  3. Reconstruction of metagenomic assembled genomes of the main organisms

Alcamán-Arias ME, Pedrós-Alió C, Tamames J, Fernández C, Pérez-Pantoja D, Vásquez M and Díez B. 2018. Diurnal Changes in Active Carbon and Nitrogen Pathways Along the Temperature Gradient in Porcelana Hot Spring Microbial Mat. Frontiers in Microbiology, 9:2353. doi: 10.3389/fmicb.2018.02353

Guajardo-Leiva, Sergio, Carlos Pedrós-Alió, Oscar Salgado, Fabián Pinto, Beatriz Díez. 2018. Active crossfire between Cyanobacteria and Cyanophages in phototrophic mat communities within hot springs. Frontiers in Microbiology, 9:2039. doi: 10.3389/fmicb.2018.02039

Mackenzie, R., C. Pedrós-Alió, B. Díez (2013) Bacterial composition of microbial mats in hot springs in Northern Patagonia: variations with seasons and temperature. Extremophiles 17: 123-136. DOI 10.1007/s00792-012-0499-z

In Santiago de Chile:

Beatriz Díez, Pontificia Universidad católica de Chile


In San José, Costa Rica:

Lorena Uribe, Universidad de Costa Rica


In Cuzco, Perú:

María Antonieta Quispe, Universidad Nacional de San Antonio Abad del Cuzco


Cold environments

Icebreaker CCGS Amundsen in Franklin Bay (Canada) and iceberg in the Weddell Sea (Antarctica)

Polar oceans are not only cold, but they are ice-covered and in the dark for a part of the year. Temperature increases due to climate change are faster in the Arctic than in the rest of the globe. Understanding the functioning of ecosystems particularly during the winter is essential to model the future of the Polar seas.

We study the adaptations and gene expression of microbes as conditions change from winter to summer

  1. Iron wars along the winter to spring transition in Cambridge Bay, Canada
  2. The role of proteorhodopsins in the Arctic
  3. Physiological ecology of marine Flavobacteria

Pedrós-Alió, Carlos, Marianne Potvin & Connie Lovejoy (2015) Diversity of planktonic microorganisms in the Arctic Ocean. A review. Progress in Oceanography 139: 233-243. http://dx.doi.org/10.1016/j.pocean.2015.07.009

Nguyen, D., R. Maranger, V. Balagué, M. Coll-Lladó, C. Lovejoy and C. Pedrós-Alió (2015). Winter diversity and expression of proteorhodopsin genes in a Polar Ocean. ISME Journal, 9 (8): 1835-1845. doi:10.1038/ismej.2015.1

Alonso-Sáez, L, A S Waller, D R Mende, K Bakker, H Farnelid, P Yager, C Lovejoy, J-É Tremblay, M Potvin, F Heinrich, M Estrada, L Riemann, P Bork, C Pedrós-Alió, S Bertilsson (2012) Role for urea in nitrification by polar marine Archaea. Proceedings of the National Academy of Sciences USA 109 (44) 17989-17994; doi:10.1073/pnas.1201914109

In Canada:

C.J. Mundy, University of Manitoba, Winnipeg, Canada


In Barcelona:

Silvia G. Acinas, Institut de Ciències del Mar, CSIC


In La Laguna, Tenerife, Spain

José M. González, Universidad de La Laguna


Hypersaline environments

Crystallizer ponds at El Litio (Chile) and Santa Pola (Alicante).

Salinity is between 10 and 30 times higher in solar salters than in the sea.
A fascinating community of only a few bacteria and archaea reach huge concentrations in the crystallizer ponds. This allows detailed analysis of the community.

  1. Application of generalized Lotka-Volterra models to identify co-varying microbial species
  2. Carbon flow along salinity gradients
  3. The limit of life in lithium solar salterns

Escudero, L.V., E.O. Casamayor, C.S. Demergasso, G. Chong, C. Pedrós-Alió. (2013) Distribution of microbial arsenic reduction, oxidation and extrusion genes along a wide range of environmental arsenic concentrations PLOS one, e78890 8: 1-14

López-López, A., Richter, M., Peña, A., Tamames, J., Rosselló-Móra, R. (2013) New insights into the archaeal diversity of a hypersaline microbial mat obtained by a metagenomic approach. Systematic and Applied Microbiology, 36 (3): 205-214. DOI: 10.1016/j.syapm.2012.11.008

Pedrós-Alió, C. 2005. Diversity of microbial communities: the case of solar salterns. In: N. Gunde-Cimerman, Ana Plemenitas and A. Oren (eds.) Cellular Origins, Life in Extreme Habitats and Astrobiology (COLE), edited by Joseph Seckbach, volume 9, pp. 71-90

In Alicante, Spain:

Josefa Antón, Universidad de Alicante


In Antofagasta, Chile:

Cecilia Demergasso, CICITEM