Friday, January 09, 2009

Fascinating Stuff You Didn't Know About Bacteria

The count of bacteria on our planet vastly outnumbers all other life forms combined. One scientific source pegs them around five million trillion trillion strong.

Placed end to end, earth's bacteria would stretch from here to the edge of the visible universe, about ten billion light years away.

You will find bacteria virtually everywhere you look. That includes in your body. You likely know bacteria as invaders, causers of disease. Pharmaceutical companies and television advertising promote that understanding. It's only partly true.

We couldn't live without bacteria--the good kind. Our bodies are really symbionts, part human cells and part bacteria. Our body cells provide the living environment and nutrition for the good bacteria, while they provide protection from many diseases for us.

Those television commercials where graphics show bacteria in the mouth, with actors in white coats making grimacing faces to show how ugly and dangerous the bacteria are deceive us. The mouth is the first line of defence against disease. Good bacteria in the mouth hunt down and kill the bad bacteria before they get any further and acquire a foothold. Those antibacterial mouthwashes kill bad bacteria, as advertised. They also kill far more good and beneficial bacteria whose primary function is to kill the bad ones. Good bacteria in the mouth always vastly outnumber the bad ones, except when both are killed off by antibacterial mouthwashes.

Most cases of bad breath--halitosis--result from dead bacteria and partly broken down food particles on the back of the tongue. Just as you blow your nose when you have a cold to remove the detritus of the battles in your body of good bacteria against bad, you should brush your tongue--especially the back of the tongue that gets little activity--to remove rotting matter.

Mints, gum and eating food either mask problems on the back of the tongue or delay their giving off a bad odour until the mouth is quiet during the night. Morning breath is usually caused by food and dead bacteria rotting away on the back of the tongue during the night. Brush the tongue before bed at night and your breath will likely be much fresher in the morning.

Removing bacteria in the mouth that have given their lives to save yours is like taking out the trash. What the trash was originally was good and beneficial, but there comes a time to get rid of what is no longer useful before it causes other problems. Do that with a brush or scraper, not with an antibacterial mouthwash weapon of mass destruction.

I used to get horrified reactions from readers when I wrote that there are likely more bacteria in our bodies than native cells. Recent estimates based on lab research suggest that bacteria in our bodies outnumber our body's cells by a factor of ten.

Bacteria are the oldest known life form. They have been on earth for 3.5 billion years, since shortly after the surface of our planet solidified.

They were the source of mystery, speculation and superstition until 1674 when Dutch scientist Antonie van Leeuwenhoek invented the first microscope and spotted the first "animacules." Some were microbes (including bacteria), some spermatozoa and some blood corpuscles.

Some varieties of bacteria are remarkably adept at reproduction. They can go from birth to being capable of reproduction themselves in ten minutes. A single bacterium could theoretically be the progenitor of more than one billion offspring within five hours. They don't reproduce sexually, so they don't require recovery time. They don't seem to require sleep or rest. They're just full time busy bodies.

There may be more varieties of bacteria as yet unidentified than we have listed of all other known species of life. In 2003, geneticist J. Craig Ventner travelled several oceans of the world scooping up water samples from the surfaces. On examination of his water samples he found more than one million bacterial genes never seen before.

Ventner is leading a team that plans to build a bacterium from scratch. His first created "life form" is under study now.

Why do we need to create more bacteria when we have so many we haven't even found? Remember how some bacteria live so well in our bodies, killing the bad guys that invade us? Some new bacteria could be designed to kill cancer cells, for example. Other researchers are genetically modifying viruses for similar purposes. Some day, curing your newly identified cancer or tuberculosis or cholera may require nothing more than getting a needle in the doctor's office.

Bacteria are fast. E. coli, one of the feared kind but also one of the varieties being genetically modified to help us, can travel 25 times it's own length in one second.That would be like a race horse galloping at 135 miles per hour (216 kph).

Bacteria have been with us and in us for so long that some have been incorporated into our bodies. Mitochondria, an organelle with enzymes that power every cell in our bodies, descended from bacteria. Stretches of our own DNA are virtually identical to the DNA of certain bacteria and viruses. Bacteria may be responsible for allowing our bodies to incorporate virus DNA into our own.

Science is totally rethinking the use of antibiotics to cure our problems. At one time given out freely by doctors to address patient problems they couldn't figure out, including viral infections that cannot be addressed by antibiotics, antibiotics are now recognized as having been abused and misused, resulting in the so-called superbug bacteria that no antibiotic can touch.

Clostridium difficile (better known as C. difficile or C. diff), the terror of some modern hospitals, moves in and takes over a body when its natural defences have been destroyed by antibiotics or immune system failure. It causes painful inflammation in the gut, diarrhea and even death.

Bacteria are so good at adapting to avoid the effects of antibiotics--thus gaining the title superbug--that one superbug bacteria known as MRSA killed 19,000 Americans in 2005 alone.

Floating bacteria have the unusual characteristic of being the "germ" around which moisture collects in the air. One theory, as yet unproven, recommends that bacteria be sprayed onto clouds to "seed" them, causing rain in areas of drought. The problem with testing the theory is that many people believe that all bacteria are bad, a belief they learned from deceptive television commercials.

Bacteria are amazingly resilient. They have been found two miles down in a South African gold mine, living off energy given off by radioactive rocks. Deinococcus radiodurans can survive 10,000 times as much radiation as humans, making it a prime subject for study about cleaning up nuclear waste. Other varieties have been found under two kilometres of ice in the Antarctic and revived, having laid under the ice for hundreds or even thousands of years.

Australian scientists have discovered that Ralstonia metallidurans can turn gold dissolved in a liquid into solid gold nuggets.

Bacteria may even one day not just power, but be the computer you use. As single-purposed and diligent as they are, they can follow directions without close supervision. E. coli has already been assembled as part of a computer, to produce a bull's-eye on command.

No word yet on whether the bacteria will run Windows or Linux.

Bill Allin
Turning It Around: Causes and Cures for Today's Epidemic Social Problems, a guidebook for parents and teachers who want to know what kids need while they are growing, not just what they should be taught to get good jobs as adults.
Learn more at http://billallin.com

[Primary source: Discover, December 2008]

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