Ancient gene planted in modern bug to track evolutionJuly 12th, 2012 - 9:35 pm ICT by IANS
Washington, July 12 (IANS) US researchers have resurrected a 500-million-year-old gene from bacteria and inserted it into modern-day E. coli bug to see whether the evolutionary trajectory once taken will repeat itself or whether a life will adapt following a different path.
They relied on a process called paleo-experimental evolution. The bug has now been growing for more than 1,000 generations, giving the scientists a front seat to observe evolution in the real world, just as Jurassic Park did with the reel version.
“This is as close as we can get to rewinding and replaying the molecular tape of life,” said scientist Betul Kacar, NASA astrobiology postdoctoral fellow in Georgia Institute of Technology NASA Centre for Ribosomal Origins and Evolution.
“The ability to observe an ancient gene in a modern organism as it evolves within a modern cell allows us to see whether the evolutionary trajectory once taken will repeat itself or whether a life will adapt following a different path,” said Kacar.
In 2008, Kacar’s postdoctoral advisor, Eric Gaucher, associate professor of biology, successfully determined the ancient genetic sequence of Elongation Factor-Tu (EF-Tu), an essential protein in E.coli, according to a Georgia statement.
EFs are one of the most abundant proteins in bacteria, found in all known cellular life and required for bacteria to survive. That vital role made it a perfect protein for the scientists to answer questions about evolution.
After placing the ancient gene in the correct chromosomal order and position in place of the modern gene within E. coli, an extremely difficult task, Kacar produced eight identical bacterial strains and allowed “ancient life” to re-evolve.
“The altered organism wasn’t as healthy or fit as its modern-day version, at least initially,” said Gaucher, “and this created a perfect scenario that would allow the altered organism to adapt and become more fit as it accumulated mutations with each passing day.”
The growth rate eventually increased and, after the first 500 generations, the scientists sequenced the genomes of all eight lineages to determine how the bacteria adapted. Not only did the fitness levels increase to nearly modern-day levels, but also some of the altered lineages actually became healthier than their modern counterpart.
“We think that this process will allow us to address several longstanding questions in evolutionary and molecular biology,” said Kacar.
These results were presented at the recent NASA International Astrobiology Science Conference.
- Bison bones show adaptability to climate change - Feb 01, 2012
- Scientists isolate molecule that helps produce proteins - Feb 15, 2011
- Scientists recreate billion-year-old enzyme - Nov 01, 2011
- Slow and steady really does win the race - Mar 23, 2011
- Mechanism affecting Salmonella virulence, drug susceptibility discovered - Jul 30, 2010
- NASA Finds Traces Of Life In One Of Saturn's Moon, Reports Say - Dec 02, 2010
- How ancient species adapted to life in open oceans - Sep 17, 2009
- New 'tree of life' constructed for one of the largest groups of bacteria - May 18, 2010
- NASA Announces Existence Of Bacteria Thriving On Arsenic - Dec 03, 2010
- Greater adaptability key to survival - Mar 23, 2011
- How we become altruistic - Sep 22, 2010
- Polar bears evolved recently and adapted quickly, reveals ancient DNA - Mar 02, 2010
- Protein switch that kills deadly water-based pathogens discovered - May 27, 2010
- Scientists decode genomes of sexually precocious fruit flies - Sep 17, 2010
- Discovery paves way for safer drinking water, cheaper medicine - May 27, 2010
Tags: abundant proteins, bacterial strains, cellular life, different path, e coli, efs, elongation factor, evolutionary trajectory, experimental evolution, front seat, genetic sequence, georgia institute of technology, jurassic park, kacar, nasa, nasa centre, paleo, perfect protein, postdoctoral advisor, reel version