posted on Apr, 12 2012 @ 06:49 PM
Researchers delved deep down into Lechuguilla Cave, a maze of tunnels that run more than 130 miles, in Carlsbad Caverns National Park which is located
in southeastern New Mexico.
The team sought out to collect and study various strains of bacteria that made their home in the caves. "Untouched by humans for all of their 4
million years, these strains of bacteria thrive on the harsh minerals of the geological formations to which they cling and fend off other life forms
that would prey on them." Understand that these bacteria have absolutely no interaction with sunlight and very little exposure to water, save for the
sparse amount of moisture in the air.
Scientists who collected 93 strains of bacteria from the forbidding depths of Lechuguilla found that all were resistant to at least one of the
antibiotics that modern medicine uses to fight bacterial infections and some were resistant to at least 14. In addition, virtually all of the 26
antibiotics tested as part of the study proved useless in killing at least one of the strains of bacteria collected.
That these life forms evolved in ways that appear to anticipate medicines attests to bacteria's remarkable powers of survival. It also suggests that
the rise in antibiotic- resistant diseases isn't due entirely to the runaway use of these drugs; rather, try as you might to kill them, bacteria are
programmed to endure.
The findings make it clear that humans will always have to contend with the problem of antibiotic resistance, no matter what steps are taken to
prevent it, said Dr. Brad Spellberg, an infectious disease researcher at the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center:
"There's never going to be a point where we can say, 'OK, we're up, we're ahead, they're done.' "
Researchers have harvested bacteria on the Earth's surface that was thousands of years old and reported last year that some of them were resistant to
antibiotics. That might have been due to exposure to natural antibiotic threats in their environment.
"This pushes it way back," Spellberg said.
Barton's samples were kept alive in lab dishes that approximated their nutrient-poor origins. The 93 strains that survived and were chosen for
evaluation were subjected to 26 antimicrobial agents, ranging from natural products such as vancomycin to completely synthetic agents such as
ciprofloxacin and linezolid.
In one group of bacterial strains — the "gram-positive" strains — 70% of the samples were resistant to between three and four classes of
antibiotics, on average. The same was true of 65% of the "gram-negative" strains.
Tetracycline antibiotics were effective against all of the bacterial samples. But sulfamethoxazole, trimethoprim and fosfomycin were not. Three
ancient strains of bacteria in the Streptomyces genus proved resistant to daptomycin, the newest class of antibiotic approved for clinical use.
Certainly, findings like these shed new light on how resilient these organisms can be, especially how they are able to thrive for millennia in such
seemingly inhospitable environments.
I thought this quote was interesting and relevant on its own:
Spellberg said the findings underscore the need for measures like the one taken Wednesday by the FDA. In 2010, the agency said that nearly 29
million pounds of antibiotic agents were fed to the nation's livestock each year. That practice accelerates bacteria's adaptation to the drugs, he
Source: LA Times
edit on 4/12/12 by Resonant because: (no reason given)