Oceans
In the last decade, round the world sampling programs have been launched and massive sequencing has been used to tackle the enormous diversity of marine microbes. The International Census of Marine Microbes (2005-2010) was the first to use high throughput sequencing to retrieve marine diversity. At about the same time, the Sorcerer II Global Ocean Sampling expedition (http://www.jcvi.org/cms/research/projects/gos/overview/) collected surface samples from several oceans. More recently TARA Oceans (https://www.embl.de/tara-oceans/start/) and Malaspina 2010 (http://www.expedicionmalaspina.es/Malaspina/Main.do#content:Home), have collected samples down to 1000 and 4000 meters respectively, mostly in the tropical and subtropical oceans. All of these efforts have resulted in a huge data set of sequences from the oceans that can now be queried for different ecological questions.
We use marine data to identify potentially interacting microbial taxa through co-occurrence networks. Link to projects.
Stations sampled during circumnavigation cruises Maslapina 2010 and Tara Oceans.
We use metagenomes to assemble genomes of environmentally relevant bacteria and to look at seasonal changes in the abundance of different taxa and different functions.
We also use sequence information to analyze microdiversity. We analyze the existence of different strains of chosen organisms adapted to different ecological situations. We use metagenomic information of genes and deconvolution to reconstruct the genetic variability within particular species. Link to projects.
Extreme Environments
Extreme environments demand specific adaptions of the organisms living in them. Along evolution, only a small set of microbial taxa has been able to adapt to such conditions. Therefore, microbial communities are simplified in extreme environments. As an example, there may be 3,000 bacterial and archaeal taxa in a sample of marine water. A similar sample from our gut will contain 300 taxa and a sample from a hypersaline environment has only 10 to 30 taxa. This simplifies the potential interactions among microorganisms and facilitates our objective of analyzing microbial communities
Geyser and microbial mats at El Tatio (4200 masl, northern Chile)
Human body
The fundamental importance of our microbiota has not been realized until the last couple of decades. Microorganisms cover our body and live inside it. Their contribution to our health depends on a delicate balance with pathogens and the immune system. We are interested in the interactions between pairs of microorganisms in our body, since these interactions will be similar to those in other environments.
We study physical interactions among gut bacteria by encapsulating them in microspheres and looking at their capacity for growing together. We are also interest in the diversity and metabolic interactions of the normal microbiota in the mouth and the vagina.
Art by Charis Tsevis (http://tsevis.com/; reproduced with permission)
Other environments
Our techniques can be applied to any environment. Thus, we collaborate with scientist interested in several other environments, such as wastewaters, bioleaching piles, or plastics.