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The Bold Traveler October 19, 2008

Posted by Mrs Weird Scientist in Environment, Microbes, Think About It.
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Imagine a world where you are all alone and surrounded by complete and total darkness. Now, take away all of your oxygen. Sound scary? Not necessarily. For the Desulforudis audaxviator – or bold traveler – this is the normal way of life. This bug relies on some important things for its survival: water, hydrogen and sulphate. It was recently discovered by a group of scientists led by Dr Dylan Chivian of California’s Lawrence Berkeley National Laboratory. The results of the research were published in the journal Science.

J. Craig Venter Institute, and Gordon Southam, University of Western Ontario

Credit: Greg Wanger, J. Craig Venter Institute, and Gordon Southam, University of Western Ontario. This lonely baterium travels in complete darkness.

So, why should we care about this lonely bug that braves its world alone? Well, if we think about how this rod-shaped bacterium can survive without oxygen, we might be able to get some important clues about whether life exists on other planets. If we found life on other planets, we would maybe learn that those bugs and creatures are able to get by without oxygen while still obtaining energy from chemicals such as sulphate.

Excited Scientists

Let me tell you, scientists were really excited when they discovered the bacterium. But, it wasn’t easy! They found it 1.74 miles (2.8 km) below the Earth’s surface near Mponeng mine, which is close to Johannesburg, South Africa. The bug was in total darkness and 60 C (140 F) heat. Now that’s hot! Scientists originally found the bacterium in DNA that was drawn from cracks in the mine – filled with water. Who would have thought that it would be a gold mine where scientists would discover the first ecosystem that only has one biological species? Sometimes, it seems that darkness can be full of special surprises and this is especially true in the case of our bold, lonely traveler.

A Day In The Life Of The Lonely Traveler

Since our isolated bacterium lives all alone, it has to get organic molecules without any help from other species. To do this, it builds what it needs to survive from water, inorganic carbon and nitrogen. These are all sourced from ammonia in the nearby rocks and fluid. But it sure does live deep in the Earth, doesn’t it? Thanks to evolution, our traveling friend can handle all sorts of tough situations and conditions. Over time, it has developed ways to handle stuff like fixing nitrogen straight from elemental nitrogen in the environment.

But wait, it can’t do everything. This smart bacterium can’t handle oxygen, which tells scientists that it has been without oxygen for a really long time. I guess that the lengthy journey into the Earth has toughened it up to lots of harsh conditions. However, without oxygen exposure, there was no need for it to develop any mechanism to resist it. Still, it continues to survive and hints to us that there could be a lot more bugs and creatures out there that manage to get by just fine without oxygen and many of the basic things we associate with life. Now that’s adaptation!

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Cleaning Up Cuts January 23, 2008

Posted by Mrs Weird Scientist in Easy As Pie, Human Body, Microbes.
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Oooow. Wounds are never fun and they are a big part of medical care. On top of that, it can be a challenge to keep them free from infection while also promoting healing. So, how are wounds kept clean? Antiseptic? Tap water? Salt water? Nothing at all? There has been some debate for a while now about the best way to clean a cut, which can ensure that it heals effectively and doesn’t get infected. As with many things in science, it’s hard to get all of those bickering scientists to agree!

Fixing Up That Cut

Wound Some studies have shown that using an antiseptic seems to slow down the rate of healing, which has prompted others to recommend using saline – also known as salt water. But there’s another concern about saline as well. It’s thought that saline could wash away some of the important growth promoters and white blood cells. This means that healing could slow and your body’s natural ability to fight infection with white blood cells could be compromised by using saline. Others have addressed the issues regarding saline and antiseptic with a completely different suggestion. Tap water! The idea is to use tap water or clean, boiled water.

Tell Me More

According to a Cochrane Review, using tap water to clean wounds does not increase infection rates. Keep in mind, however, that it also doesn’t reduce the infection rate or increase the rate of healing in comparison with doing nothing at all – basically leaving the wound alone. Researchers checked out eleven trials that compared healing and infection rates from a range of cleaning styles. Wounds that were cleaned with tap water had fewer infections in comparison with those cleaned with saline. But, as I mentioned earlier, there wasn’t any difference between the wounds cleaned with tap water and those that weren’t cleaned at all. According to Ritin Fernandez, the main author of the study who works at the Centre for Applied Nursing Research in Liverpool, Australia:

The decision to use tap water to cleanse wounds should take into account the quality of water, nature of wounds and the patient’s general condition.

Your Skin Is A Barrier

Plain and simple – wounds hurt! If infection strikes, the pain increases and other complications can occur. Slow healing is also a problem because it means that one of your most important barriers to microbes and viruses is not in its toughest state. Fortunately, we’ve got researchers studying our wounds to find out the best way to treat them and get our skin back to its healthiest, protective form. Now, if only they could find a way to quiet the babies like me who squeal from even the smallest paper-cut!

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Saved By An Earthquake January 21, 2008

Posted by Mrs Weird Scientist in Environment, Evolution, Microbes.
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When we think of earthquakes, I’m guessing most of us think about injuries, death and widespread damages. But for some living creatures, earthquakes are what actually keep them alive! For these miniscule microbes, earthquakes could provide the important nutrients they need to live.

Crusts Are Good

No, I’m not talking about bread! The earth’s crust is home to some tough bacteria that live many kilometers below the surface. Down, down, down into the depths of the earth, these microbes live without sun or organic materials to support their requirements. What keeps them alive? They live off chemical energy from reactive molecules. These molecules include hydrogen, which dissolves in the water that leaches from the rock.

I Like The Way You Move

Two researchers from Stanford University in California have suggested that the movement from earthquakes may play a valuable role in keeping microbes who reside deep in the earth’s crust alive. Calculations by Norman Sleep and Mark Zoback showed that seismic activity may occur often enough to consistently provide nutrients across a tectonic plate. This means that microbial life could continue for billions of years! By opening up cracks in the earth’s crust, earthquakes can release little pockets of water that are rich in the favorite nutrients of the microbes. Not only that, but the movement can expose rock that has the dissolved hydrogen these microbes adore so much. Yum!

Applying Research To Other Planets

What happens here on the earth can give us some cool clues to the stuff happening on other planets. How so? Well, the researchers think that this same mechanism could be sustaining microbes deep in the crust on planets like Mars. So, while you and I live happily on the earth’s surface, microbes are partying it up in the depths of the earth’s crust!

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