Research Primer

Analogue Environments

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Analogue environments are places on Earth that are similar to places on other planets or moons in our solar system and beyond. Analogue environments may also mimic conditions on Earth during different times of our geologic history, including when life first arose some 4.3 billion years ago. Many of these environments are considered extreme and can include conditions such as:

  • very hot or cold temperatures; ex. hydrothermal vents and pools, or antarctic ices and lakes

  • very dry conditions (ie little to no water); ex. hot or cold deserts

  • hypersaline waters; ex. brine pools or salt lakes

 

Extreme environments, such as a the deep subsurface, are considered low-biomass so life is difficult detect due to the low number of individual organisms (or cells). To determine whether a sample has microbes in it I use so-called biosignatures which are molecules that are made by living organisms. Primarily I use phospholipid fatty acids (PLFA) which are derived from the lipids of cellular membranes. Using a solvent-based extraction I am able to identify and quantify the PLFA in a sample using gas chromatography - mass spectrometry (GC-MS). This allows me to approximately determine how many cells are present and, in combination with stable carbon isotopes, also provides some information on the metabolism(s) the organisms are using.

Biosignatures

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Kidd Creek Mine

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Part of my research involves working in the field in order to both set-up apparatus and to collect samples at the end of the sampling period. One of my field sites is the Kidd Creek Mine in Timmins, Ontario, Canada. At an approximate depth of 2.4km below the surface, hypersaline water was discovered that has a mean residence time (MRT) of 1.4 billion years. As part of my MSc. I was tasked with filtering this water and extracting the filters for membrane-derived phospholipid fatty acids (PLFA). This work is ongoing, with further analysis of these samples including nucleic acid analysis to determine what types of organisms may be living at the fluid-mine interface.