On the Response of Halophilic Archaea to Space Conditions

Abstract

Microorganisms are ubiquitous and can be found in almost every habitat and ecological niche on Earth. They thrive and survive in a broad spectrum of environments and adapt to rapidly changing external conditions. It is of great interest to investigate how microbes adapt to different extreme environments and with modern human space travel, we added a new extreme environment: outer space. Within the last 50 years, technology has provided tools for transporting microbial life beyond Earth’s protective shield in order to study in situ responses to selected conditions of space. This review will focus on halophilic archaea, as, due to their ability to survive in extremes, they are often considered a model group of organisms to study responses to the harsh conditions associated with space. We discuss ground-based simulations, as well as space experiments, utilizing archaea, examining responses and/or resistance to the effects of microgravity and UV in particular. Several halophilic archaea (e.g., Halorubrum chaoviator) have been exposed to simulated and actual space conditions and their survival has been determined as well as the protective effects of halite shown. Finally, the intriguing potential of archaea to survive on other planets or embedded in a meteorite is postulated.

Survival of halophilic Archaea in Earth's cold stratosphere

“…The recent discovery of brine flows on the surface of Mars has intensified interest in the extremophilic character of extremely halophilic microorganisms in relation to astrobiology (Mancinelli et al 2004; DasSarma 2006; Horneck et al 2010; Leuko et al 2014). Flowing brines were first noted as seasonal dark streaks or recurring slope lineae (RSL) on the walls of Garni crater observed from images captured by NASA's Mars Reconnaissance Orbiter (McEwen et al 2011).…”

The Human Microbiota and the Immune System; Reflections on Immortality

“…Will it be the end of it? I do not think so: microbes survive quite well in the outer space, thrive in the tails of comets and outside human space stations [22]. The concept of panspermia [23].…”

Biotechnological potentials of halophilic microorganisms and their impact on mankind

“…Salty water pockets and frigid water acquirers near South Martian poles are packaged with manganese and calcium perchlorate which is most likely to be habitable for halophilic bacteria [ 103 ]. Molecular structure resembles that haloarchaeon, Halorubrum chaoviator , could survive in freezing and thawing brine in Mars [ 104 ]. The archaea with higher tolerance to perchlorate (upto 0.4 M), can use chlorate as terminal electron acceptor during anaerobic respiration [ 105 ].…”