Team discovers adaptations to explain strategies for survival on Mars

Mar 11, 2013
Mars

Research from the University of Maryland School of Medicine has revealed key features in proteins needed for life to function on Mars and other extreme environments.

The researchers, funded by NASA, studied that survive in the extreme environment of Antarctica. They found subtle but significant differences between the core proteins in ordinary organisms and Haloarchaea, organisms that can tolerate severe conditions such as high salinity, desiccation, and . The research gives scientists a window into how life could possibly adapt to exist on Mars.

The study, published online in the journal on March 11, was led by Shiladitya DasSarma, Ph.D., Professor in the Department of Microbiology and Immunology at the University of Maryland School of Medicine and a research scientist at the Institute of Marine and .

Researchers found that Haloarchaeal microbes contain proteins that are acidic, with their surface covered with negatively charged residues. Most ordinary organisms contain proteins that are neutral on average. The found in the unusual organisms keep proteins in solution and help to hold on tightly to water, reversing the effects of high salinity and desiccation.

In the current study, the scientists identified additional subtle changes in the proteins of one Haloarchaeal species named Halorubrum lacusprofundi. These microbes were isolated from Deep Lake, a very salty lake in Antarctica. The changes found in proteins from these organisms allow them to work in both cold and salty conditions, when temperatures may be well below the freezing point of pure water. Water stays in the under these conditions much like snow and ice melt on roads that have been salted in winter.

"In such , the packing of atoms in proteins must be loosened slightly, allowing them to be more flexible and functional when ordinary proteins would be locked into inactive conformations" says Dr. DasSarma. "The surface of these proteins also have modifications that loosen the binding of the surrounding water molecules."

"These kinds of adaptations are likely to allow microorganisms like Halorubrum lacusprofundi to survive not only in Antarctica, but elsewhere in the universe," says Dr. DasSarma. "For example, there have been recent reports of seasonal flows down the steep sides of craters on Mars suggesting the presence of underground brine pools. Whether microorganisms actually exist in such environments is not yet known, but expeditions like NASA's Curiosity rover are currently looking for signs of life on Mars."

"Dr. DasSarma and his colleagues are unraveling the basic building blocks of life," says E. Albert Reece, M.D., Ph.D., M.B.A., Vice President for Medical Affairs at the University of Maryland and John Z. and Akiko K. Bowers Distinguished Professor and Dean of the University of Maryland School of Medicine. "Their research into the fundamentals of microbiology are enhancing our understanding of life throughout the universe, and I look forward to seeing further groundbreaking discoveries from their laboratory."

Explore further: SDO captures images of two mid-level flares

More information: Dr. DasSarma and his colleagues are conducting further studies of individual proteins from Halorubrum lacusprofundi, funded by NASA. The adaptations of these proteins could be used to engineer and develop novel enzymes and catalysts. For example, the researchers are examining one model protein, β-galactosidase, that can break down polymerized substances, such as milk sugars, and with the help of other enzymes, even larger polymers. This work may have practical uses such as improving methods for breaking down biological polymers and producing useful materials (see Karan et al. BMC Biotechnology 2013 13:3 www.biomedcentral.com/1472-6750/13/3).

Related Stories

Australian lakes may hold clues to life on Mars

Jan 05, 2010

(PhysOrg.com) -- By the time Curiosity, the next Mars Rover, launches in 2011, scientists on Earth will know more about the potential for life on Mars because of microorganisms that live in Australian lakes.

Microbial life on Mars: Could saltwater make it possible?

Aug 17, 2011

(PhysOrg.com) -- How common are droplets of saltwater on Mars? Could microbial life survive and reproduce in them? A new million-dollar NASA project led by the University of Michigan aims to answer those questions.

Carbon-consuming life-forms in Antarctica

Apr 23, 2012

Lake Bonney in Antarctica is perennially covered in ice. It is exposed to severe environmental stresses, including minimal nutrients, low temperatures, extreme shade, and, during the winter, 24-hour darkness. ...

Asteroid sites hint at life on Mars

Apr 16, 2012

(Phys.org) -- Craters made by asteroid impacts may be the best place to look for signs of life on other planets, a study suggests.

Could life survive on Mars? Yes, microbiologist says

Jun 04, 2010

Researchers at McGill's department of natural resources, the National Research Council of Canada, the University of Toronto and the SETI Institute have discovered that methane-eating bacteria survive in a ...

Melt water on Mars could sustain life

Nov 16, 2012

Near surface water has shaped the landscape of Mars. Areas of the planet's northern and southern hemispheres have alternately thawed and frozen in recent geologic history and comprise striking similarities ...

Recommended for you

SDO captures images of two mid-level flares

Dec 19, 2014

The sun emitted a mid-level flare on Dec. 18, 2014, at 4:58 p.m. EST. NASA's Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts ...

Why is Venus so horrible?

Dec 19, 2014

Venus sucks. Seriously, it's the worst. The global temperature is as hot as an oven, the atmospheric pressure is 90 times Earth, and it rains sulfuric acid. Every part of the surface of Venus would kill you ...

Image: Christmas wrapping the Sentinel-3A antenna

Dec 19, 2014

The moment a team of technicians, gowned like hospital surgeons, wraps the Sentinel-3A radar altimeter in multilayer insulation to protect it from the temperature extremes found in Earth orbit.

Video: Flying over Becquerel

Dec 19, 2014

This latest release from the camera on ESA's Mars Express is a simulated flight over the Becquerel crater, showing large-scale deposits of sedimentary material.

Spinning up a dust devil on Mars

Dec 19, 2014

Spinning up a dust devil in the thin air of Mars requires a stronger updraft than is needed to create a similar vortex on Earth, according to research at The University of Alabama in Huntsville (UAH).

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.