The Ground-Based BIOMEX Experiment Verification Tests for Life Detection on Mars

Area of Science:

• Astrobiology
• Planetary Science
• Microbiology

Background:

• Astrobiological missions require reliable methods for detecting biosignatures, which are traces of past or present microbial life.
• Spectroscopic techniques offer non-destructive, repeatable, and remote analysis suitable for extraterrestrial environments.

Purpose of the Study:

• To evaluate the efficacy of Raman and Fourier Transform Infrared (FT-IR) spectroscopies in detecting fungal biosignatures under simulated Martian conditions.
• To assess the impact of UV irradiation on the detectability of DNA, melanin, and chitin in the fungus Cryomyces antarcticus.

Main Methods:

• Culturing Cryomyces antarcticus on Martian analogue substrates.
• Exposing fungal colonies to increasing doses of UV irradiation under dried conditions.
• Analyzing samples using Raman and FT-IR spectroscopies.
• Employing complementary analytical techniques for pigment identification.

Main Results:

• Significant UV-induced DNA damage was observed, but DNA remained amplifiable and detectable.
• Spectral properties of fungal melanin were unaltered, allowing for pigment identification.
• Fungal cell wall compounds, primarily chitin, showed resistance to degradation and remained detectable after high UV doses.

Conclusions:

• Raman and FT-IR spectroscopies are effective tools for detecting fungal biosignatures in simulated extraterrestrial environments.
• Key biomolecules like DNA, melanin, and chitin exhibit resilience to UV radiation, enhancing the prospects for biosignature preservation and detection on planetary bodies.
• The findings have significant implications for the design and success of future astrobiological missions searching for life beyond Earth.