Molecular Genetics, Extremophiles, and Ecophysiology
The development of new sequencing technologies has permitted a greatly increased understanding of the complexity of microbial diversity as well as their functional role. In extreme environments microorganisms exhibit unusual properties and adaptations that have great value and potential for biotechnological applications. To fully utilize this potential, it is crucial to understand how the ecosystem functions in order to predict and design new applications. In Chile there are many environments that exhibit extreme conditions that represent a source of new microorganisms and bioactive compounds. We are using multiple approaches to supply the pipeline of discovery of new drugs, including metagenomic analyses to describe the potential for bioactive compound production from these specific environments and the subsequent culturing of rare and useful microorganisms.
We have analysed lithium brines from the Salar de Atacama (salinity up to 500 g/L) reporting different bacterial and archaeal assemblages regarding their salt content (either NaCl or LiCl2) This would be the highest saline system on Earth to date, and we are collaborating with Dr Steve Schmidt (University of Colorado Boulder, USA) in the exploration of microbial diversity of the Llullaillaco volcano.
We have a collaboration with CONAF (National Forest Corporation) at Los Flamencos National Reserve in a project to characterize the microbiology of the fragile aquatic ecosystems of this national reserve. We are characterizing and analyzing the microbial diversity of three almost unexplored salares: Salar de Tara, Salar de Pujsa and Laguna Helada.
Also we are finding new CRISPR-Cas systems in extreme environments; we are analyzing the genomes of 25 isolated bacteria from different extreme aquatic ecosystems of northern Chile in order to detect CRISPR-Cas.
The Biochemistry Group, Universidad de Antofagasta, has maintained its focus on the isolation and biochemical characterization of microorganisms and biomolecules and evaluation of plant extracts with anticorrosion activity. 1. The antioxidant activity of isomers of bacterioruberin purified from the extremely halophilic archaeon Haloterrigena sp. strain SGH1 is higher than synthetic and natural antioxidants. 2. The draft genome of Staphylococcus scuiri strain LCHXa, tolerant to molar concentrations of lithium, has been published. 3. The presence of several fungi genera in endolithic communities from Atacama halites is the main finding from new metagenomics analyses, making these microbial consortia more highly complex than previous reports. 4. The use of phycobiliproteins from Atacama cianobacteria as natural food colorants and additives is being studied. Promising advances have been achieved on the search of organic corrosion inhibitors from plant extracts.
We are actively involved in seaweed cultivation, productivity, genetics and economic assessment of seaweed farming. Based on spatial genetic and morphological variation of natural populations of the kelp Macrocystis pyrifera, we have evaluated the potential of the species for modifying some agronomic traits through controlled breeding in the context of a strain selection programme. We also put together the technical aspect that kelp farming requires, at a scale of 21 ha., and further developed an economic assessment that indicates the required productivity under different economic scenarios to become profitable. From these results the algal research group has been involved with several international partners and consultancies. We have also started to explore the relevance of genetic diversity and environmental stress factors on the productivity of red seaweeds of economic importance. We have also studied seaweed – bacteria interactions to allow us to deepen the understanding of seaweed-microbiome interaction and the extract of phlorotanins in the context of a biorefinery of Macrocystis pyrifera including the extraction of polysaccharide-hydrolyzing enzymes from macroalgae-associated microorganisms.
During the past couple of years, 3 new topics were incorporated: i) The interaction of salmon aquaculture and microbiome; ii) The effect of climate change and ocean acidification on seaweeds; iii) Algal blooms: including the impact of the harmful algal blooms (HAB) in the Chilean aquaculture Finally, this group is working in collaboration with Dr. Conca in the development of a mathematical model to predict HABs events including new algorithms to coupled satellite images with toxic algal blooms.
An algal biorefinery has been developed to produce pigments and hydrophobins as well as antioxidants and antimicrobial compounds through a green process. Also the seaweed fraction that remains after alginate extraction has been used to produce carotenoids and the conditions for production of long chain omega-3 fatty acids has been determined.