Cassaro Alessia, Pacelli Claudia, Onofri Silvano
Science and Innovation Directorate, Italian Space Agency, via del Politecnico, 00133 Rome, Italy.
Department of Ecological and Biological Sciences, University of Tuscia, Largo dell'Università snc, 01100 Viterbo, Italy.
Life (Basel). 2025 Apr 29;15(5):716. doi: 10.3390/life15050716.
The search for life beyond Earth currently hinges on the detection of biosignatures that are indicative of current or past life, with terrestrial life being the sole known example. Deoxyribonucleic acid (DNA), which acts as the long-term storage of genetic information in all known organisms, is considered a biosignature of life. Techniques like the Polymerase Chain Reaction (PCR) are particularly useful as they allow for the amplification of DNA fragments, allowing the detection of even trace amounts of genetic material. This study aimed to detect DNA extracted from colonies of an Antarctic black fungus both when (i) alone and (ii) mixed with a Sulfatic Mars Regolith Simulant (S-MRS), after exposure to increasing doses of Fe ions (up to 1 kGy). PCR-based amplification methods were used for detection. The findings of this study revealed no DNA amplification in samples mixed with Sulfatic Mars Regolith Simulant, providing important insights into the potential application of these techniques for in situ DNA detection during future space exploration missions or for their application on the Mars sample return program; it also gives input in the planetary protection discussions.
目前，对地球以外生命的探索依赖于对生物标志物的检测，这些生物标志物表明存在当前或过去的生命，地球上的生命是唯一已知的例子。脱氧核糖核酸（DNA）在所有已知生物体中作为遗传信息的长期储存介质，被视为生命的生物标志物。像聚合酶链反应（PCR）这样的技术特别有用，因为它们能够扩增DNA片段，即使是痕量的遗传物质也能被检测到。本研究旨在检测从南极黑真菌菌落中提取的DNA，检测条件为：（i）单独存在时；（ii）与硫酸化火星风化层模拟物（S-MRS）混合后，且暴露于递增剂量的铁离子（高达1千戈瑞）之后。采用基于PCR的扩增方法进行检测。本研究结果显示，与硫酸化火星风化层模拟物混合的样本中未出现DNA扩增，这为这些技术在未来太空探索任务中进行原位DNA检测或在火星样本返回计划中的潜在应用提供了重要见解；同时也为行星保护讨论提供了参考。
