Strange microbe that feeds on METEORITES could shed light on how life on Earth began and how living creatures can survive on other planets
- The microbes are able to metabolise minerals contained in space rocks
- They fed on the meteorite much faster than they did on Earth-based rocks
- The research could give insight into how microbes survive in outer space and could help colonise other planets including Mars
An organism that can feed on meteorites from outer space could shed light on the emergence of life on Earth – and how living creatures may survive on other planets.
The organism, known as Metallosphaera sedula, is a type of bacteria-like microbe that gets its energy from inorganic substances.
Researchers have discovered that M. sedula feeds on the minerals contained in meteorites faster than it feeds on those in Earth-based rocks.
The findings provide valuable insight into the conditions that allowed early life to emerge and evolve on Earth, as well as how microbes could survive in outer space.
A scanning electron microscopy image shows M. sedula cells colonizing the surface of the meteorite particles
M. sedula is known to cope well with heat and low pH levels, and previous experiments have shown it can survive in Martian soil.
Researchers from the University of Vienna decided to test it out on a 120-kilogram meteorite known as NWA 1172, which was found in Northwest Africa in 2000.
The meteorite is rich in iron – which microbes oxidise in order to respire – and other trace metals, which facilitate metabolic activity and microbial growth.
Remnants of different inorganic compounds found in the microbial cell
For comparison, similar microbes were fed samples of an Earth-based mineral called chalcopyrite, which is formed of copper, iron and sulphur.
They found that M. sedula cells metabolised on the meteorite much faster than they did on chalcopyrite.
The microbes survived and grew on the stony meteorite by consuming the metals trapped within it.
‘Meteorite-fitness seems to be more beneficial for this ancient microorganism than a diet on terrestrial mineral sources’, said astrobiologist Tetyana Milojevic from the University of Vienna, who led the study.
Meteorite dust fragments that were colonized and bioprocessed by the M. sedula archaea
The study could help shed light on the types of extraterrestrial materials that may have provided sustenance to some of the earliest life forms on Earth.
Meteorites may have delivered a variety of essential compounds facilitating the evolution of life as we know it, the researchers say.
The research team had previously used M. sedula in experiments that analysed its interactions with synthetic Mars materials.
Strains of the microbe were found to leave ‘fingerprints’ on the fake Mars matter, which contained a number of minerals representing different locations and periods in the Red Planet’s history.
The work gave important insight on the possible biogeochemical processes that may once have taken place on our red neighbour.
The new study was published in Scientific Reports.
