One of the most challenging questions in basic biology and the history of evolution and life stems from the unknown origin of the first cells billions of years ago. Though many pieces of the puzzle have been put together, this origin story remains somewhat murky. But a team of researchers from the University of Cambridge believe they've accidentally stumbled on an answer, and a very compelling one at that.
The discovery: Through routine quality control testing, a researcher working with Markus Ralser, who would eventually become the lead researcher for the project, stumbled upon signs of the metabolic process where, for all intents and purposes, there shouldn't have been. Until now, much of the science community has generally agreed that Ribonucleic acid, or RNA, was the first building block of life because it produces enzymes that could catalyze complex sequences of reactions such as metabolic action. However, Ralser's lab found the end products of the metabolic process without any presence of RNA. Instead, the findings indicate that complex and life-forming reactions like these could occur spontaneously given the right, but surprisingly simple, conditions.
"People have said that these pathways look so complex they couldn't form by environmental chemistry alone," Rasler told NewScientist. "This is the first experiment showing that it is possible to create metabolic networks in the absence of RNA."
Testing: Because Rasler's team basically stumbled upon their initial findings, they repeated the process several times and were pleasantly surprised with repeat successful outcomes. So, taking things to the next level, Rasler began working with Cambridge's Earth sciences department to determine if these processes could have occurred in the Archean Ocean, the oxygen-free world, predating photosynthesis, which covered the planet almost 4 billion years ago.
"In the beginning we had hoped to find one reaction or two maybe, but the results were amazing," said Ralser. "We could reconstruct two metabolic pathways almost entirely."
If these metabolic pathways were occurring in the absence of RNA in conditions rich with iron and other metals and phosphate, it seems increasingly likely that life could have literally started from nothing and spontaneously formed in ways until now believed impossible.
So what? "I think this paper has really interesting connotations for the origins of life," says Matthew Powner at University College London. "For origins of life, it is important to understand where the source molecules come from."
Rasler's team has been the first to show that life could literally come from nothing. Of course, in the scientific community, this could be a major advancement, albeit one that is still only a part of an overall picture that's still forming through years of continuing research. However, these findings could also potentially play into the creationism versus evolution debate. One of the holes often poked by creationists is the complex and hard-to-explain idea of life started from nothing at all, and for the most part scientific explanations have been somewhat lacking. However, these findings indicate that something from nothing might not be as far-fetched idea as it seems.
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