Title: "Microbes - Record-holders and their relevance to Origin of Life and Astrobiology"

Abstract:

How did life begin and evolve? Are we alone in this universe? Does life exist on other planets? These are very pressing questions that still remain unanswered.

One way to start unravelling these complex riddles is to study microorganisms. Microorganisms are fascinating in many ways. They are ubiquitous and found to live in the most extreme environments on Earth, places once thought to be uninhabitable. Some species even represent record-holders with regard to extremes such as temperature, salt, and radiation to name a few.

Today I will take you on a journey to some of the most extreme environments on Earth and the projects I have been working on in the field of origin of life, astrobiology, and planetary protection. These span from studying

i) hyperthermophilic microorganisms originating from black smokers and anaerobic microorganisms from Mars analogues on Earth such as permafrost from Siberia, acidic lakes and rivers in Iceland and Spain to advance our understanding of Martian habitability,

ii) hardy microorganisms posing a threat to planetary protection by surviving on spacecraft and in spacecraft assembly clean rooms, to

iii) investigating the microbial dynamics in the confined Mars500 habitat during simulated Mars flight and landing to prepare for a crewed Mars mission.

The combination of both, cultivation approaches and state of the art molecular technologies allowed to detect and characterize the microbial diversity of extreme environmental niches on Earth and spacecraft. Investigating these microbial communities and the boundaries of life is not only of crucial importance for the origin of life studies but also for astrobiology and the search for habitable conditions beyond Earth, because it allows us to get a step closer to answer the following questions: How do microorganisms survive such extremes? What are their adaptations enabling them to inhabit these environments?