20 things you didn’t know about bacteria rice, jocelyn. “20 things you didn’t know about...
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20 Things You Didn’t Know About Bacteria
Rice, Jocelyn. “20 Things You Didn’t Know About Bacteria” Discover December 2008
1. At about 5 million trillion trillion strong,
bacteria vastly outnumber all other life-
forms on earth.
2. Lined up end to end, they would
stretch some billion light-years – literally
from here to the edge of the visible universe
3. And there are always more on the way. Pseudomonas
natriegens, an ocean dwelling bacterium, can go from birth to reproduction in 10 minutes flat. In five hours a single cell could theoretically give rise to more
than one billion offspring.
4. Bacteria have been around for atleast 3.5 billion years, making them the oldest life-form on the
planet.
5. Humans didn’t catch a glimpse of them, though, until 1674, when
Dutch scientist Antonie van Leeuwenhoek spotted tiny
swimming “animacules” while fiddling with the newly invented
microscope.
6. A compelling argument for brushing: He (Leeuwenhoek)
discovered them while examining pond water and scrapings from
the human mouth.
7. Most bacteria have yet to be identified. In 2003, J. Craig
Venter began trolling the high seas and analyzing the water. On his first trip he fished out
more than a million never-before-seen bacterial genes.
8. The first artificial life-form will not be a robot but a bacterium. Not content with finding natural bacteria, Venter is leading an
effort to build a bacterium from scratch.
9. No escaping them: Your body has 10 times more bacterial cells
than human cells.
10. Can’t catch them, either. Whipping their tails, E.coli can travel 25 times their own length
in 1 second, equivalent to a horse running 135 miles per
hour.
11. Bacteria have even set up permanent camp inside our cells.
Mitochondria, the power-house that supplies energy to nearly every cell in the body, are the descendents of
bacteria that were engulfed by larger microorganisms billions of years
ago.
12. When you pop a pill to kill off a bad bug (bacterium) you kill
some good bugs too. A bacterium called Clostridium
difficile can move into the prime real estate cleared out by antibiotics, causing painful inflammation and diarrhea.
13. Bacteria are adept at developing resistance to
antibiotics. Among the deadliest of resistant bacteria is MRSA,
which killed 19,000 Americans in 2005 alone.
14. MRSA’s deadliness comes in part from a class of chemicals known as carotenoids, which
MRSA uses to fight off our immune systems. Ironically,
carotenoids are found in many healthy fruits and vegetables and
may reduce cancer risk.
15. But most bacteria are harmless, and some are even helpful in aiding our digestion.
Mice with bacteria-free intestines need to eat 41 percent more
calories than their germy counterparts.
16. Floating bacteria are extremely effective at spurring condensation, leading to snow
and rain. Some scientists propose spraying bacteria into
the clouds to end drought.
17. Certain bacteria thrive in extreme conditions. In 2006,
a probe at a South African gold mine turned up bacteria
living nearly two miles underground, subsisting on
the energy given off by radioactive rocks.
18. Another species, Deino-coccus radiodurans, can
survive almost 10,000 times the dose of radiation lethal to
humans, making it a prime candidate for the cleanup of
nuclear waste.
19. The midas touch:Australian scientists
found that a bacterium called Ralstonia metallidurans can turn dissolved gold into solid
nuggets.
20. But can they run Windows? By programming instructions into
their genes, scientists have engineered E.Coli that act like
computers, assembling into glowing bull’s eye shapes on
command.