One of the hurdles in origin-of-life theories is that thepieces that make up complex biomolecules do not readily come together bythemselves. A group of scientists proposes that diamonds provided a kind of"workbench" for biomolecule manufacturing on early Earth.
Not long after its formation, our planet was — according toastrobiologists — awash in a primordial soup that contained the rudimentaryingredients of life. The fly in the "soup" theory, however, isthat the small molecular bits likely needed outside help in order to latchtogether into the long, complex biomolecules that living organisms use.
"Diamond is totally non-toxic,an excellent biomaterial and certainly the only naturally existing materialthat is completely biocompatible on all levels — presumably the best of allpossible platforms for the formation of life," said Andrei Sommer from the University of Ulm in Germany.
Hydrogenated diamonds are just diamonds with an outercoating of hydrogenatoms, but they are not something you'll find in your local jewelry shop. Infact, the only hydrogenated diamonds currently known are all made in the lab.
"In nature, diamond hydrogenation is likely to occur inor in the vicinity of volcanoes known to emit a variety of hot gases includinghydrogen," Sommer said. The early Earth had so much volcanic activity thathe thinks it is highly probable that hydrogenated diamonds existed back then.
Sommer and his collaborators previously showed thathydrogenated diamond is very hydrophobic, or "water fearing" —meaning it pushes water away. When hydrogenated diamond is wetted, the watermolecules line up on the surface as if they were frozen into a crystal layer(an analogy might be static electricity making all the hairs on your head pointout).
Surprisingly, these crystal water layers do not disappearwhen the hydrogenated diamond is fully immersed in water. Because this is theonly natural material known to exhibit this behavior, Sommer's team proposesthat small organic molecules in the primordial soup landed on hydrogenateddiamond and were helped by its robust crystal water layers into linkingtogether to form proteins and DNA.
"So far, crystal water layers haveonly been described on hydrogenateddiamond," said Horst-Dieter Foersterling of Philipps University of Marburg,who was not involved with this work. "This is a new field of research.That this system can be helpful for the formation of biomolecules is aplausible hypothesis."
"I think it is not important that a lot of hydronenateddiamond was available," Foersterling said. "Once the first evolutionprocess has started in a very special location [such as a tiny patch ofhydrogenated diamond], and stable DNA strands have formed, a special locationis no more necessary."
