Monday, May 14, 2007
Asphalt-munching bacteria discovered
Trapped in the Rancho La Brea tar pits 28,000 years ago, the bacteria are equipped with special enzymes that can break down petroleum, environmental scientists at the University of California, Riverside report in a recent issue of Applied and Environmental Microbiology.
“Asphalt is an extreme and hostile environment for life to survive,” said Jong-Shik Kim, who initiated the study. But “these living organisms can survive in heavy oil mixtures containing many highly toxic chemicals” with no water and little oxygen, he said.
Bacteria that survive on petroleum produce methane gas as waste, so when Kim and his colleague Dave Crowley noticed the gas bubbling out of the oily soil, they knew they had found something unique.
The two eventually sequenced groups of the tar pit bacteria’s DNA to be certain. “Previously, some bacteria had been cultured from the asphalt,” Kim said, “but no one had been able to extract DNA from the asphalt to study the entire microbial community.”
To identify the bacteria and their unique enzymes, Kim and Crowley froze the tar with liquid nitrogen and then pulverized it into a powder. With the tar-hungry bacteria exposed, the scientists extracted the DNA.
“Asphalt is an extreme and hostile environment for life to survive,” said Jong-Shik Kim, who initiated the study. But “these living organisms can survive in heavy oil mixtures containing many highly toxic chemicals” with no water and little oxygen, he said.
Bacteria that survive on petroleum produce methane gas as waste, so when Kim and his colleague Dave Crowley noticed the gas bubbling out of the oily soil, they knew they had found something unique.
The two eventually sequenced groups of the tar pit bacteria’s DNA to be certain. “Previously, some bacteria had been cultured from the asphalt,” Kim said, “but no one had been able to extract DNA from the asphalt to study the entire microbial community.”
To identify the bacteria and their unique enzymes, Kim and Crowley froze the tar with liquid nitrogen and then pulverized it into a powder. With the tar-hungry bacteria exposed, the scientists extracted the DNA.
# posted by Morgan @ 11:55 AM 
