Knocking on the Door of Life

[JBeukema]

The scientists have synthesized for the first time RNA enzymes that can replicate themselves without the help of any proteins or other cellular components, and the process proceeds indefinitely....


To make the process proceed indefinitely requires only a small starting amount of the two enzymes and a steady supply of the subunits....

Not content to stop there, the researchers generated a variety of enzyme pairs with similar capabilities. They mixed 12 different cross-replicating pairs, together with all of their constituent subunits, and allowed them to compete in a molecular test of survival of the fittest. Most of the time the replicating enzymes would breed true, but on occasion an enzyme would make a mistake by binding one of the subunits from one of the other replicating enzymes. When such "mutations" occurred, the resulting recombinant enzymes also were capable of sustained replication, with the most fit replicators growing in number to dominate the mixture. "To me that's actually the biggest result," says Joyce.

That's right, evolution and natural selection among self-replicating RNA....

"What we've found could be relevant to how life begins, at that key moment when Darwinian evolution starts."....

Joyce says that only when a system is developed in the lab that has the capability of evolving novel functions on its own can it be properly called life. "We're knocking on that door," he says, "But of course we haven't achieved that."....

The subunits in the enzymes the team constructed each contain many nucleotides, so they are relatively complex and not something that would have been found floating in the primordial ooze. But, while the building blocks likely would have been simpler, the work does finally show that a simpler form of RNA-based life is at least possible, which should drive further research to explore the RNA World theory of life's origins.

Getting closer...

Journal reference:
Science Daily, Jan. 10, 2009

1. Lincoln et al. Self-Sustained Replication of an RNA Enzyme. Science, Jan 8, 2009; DOI: 10.1126/science.1167856

 

[editec]

In organic chemistry molecules often get more complex rather than less complex.

Why...it's almost as though here on earth carbon atoms got a pass from the ironclad universal law of entropy, isn't it?

I supect that the universe is overrun with lifeforms ranging in complexity from self replicating soups that eat themselves to people sitting in front of computer screens pondering how life began and more.

 

[Old Rocks]

From what I have read of the research on abiogenisis, the problem is not finding a possible path and environment in which life originated, but finding which path it actually used. Yes, the laws of the universe seem to favor the formation of life.

 

[JBeukema]

Why...it's almost as though here on earth carbon atoms got a pass from the ironclad universal law of entropy, isn't it?

Not at all. Entropy only applies to a closed system,- the universe as a whole

From what I have read of the research on abiogenisis, the problem is not finding a possible path and environment in which life originated, but finding which path it actually used. .

impossible without time travel, at least via any means yet pondered. That's like asking someone to prove scientifically thaat Abraham Lincoln existed

 

[Old Rocks]

Yep, was it a small warm pond, ocean rift zone, sea shore environement where a rift comes onshore, or some other environment that we are just not looking at yet. Or all of the above at differant times in the evolution from non-life to life?