XNA: The Synthetic Super-Cousin of DNA That Can Replicate and Store Information
The DNA double helix that we’re all familiar with is a molecular ladder made of three key parts. The backbone of phosphates that tie everything together up and down, the sugar rings (“deoxyribose”) that serve as rungs, and the bases (A, C, G, T) that invisibly bond the two strands of the helix together, head to toe.
But that helix can be broken or mutated in nature, leading to mutations. And out of all the compounds in the world that could have evolved to carry our information, why just DNA and its cousin RNA? To answer that question, Vitor Pinheiro’s team created a completely new set of information molecules called XNA.
XNA replaces the deoxyribose sugar ring with other chemical rings like threose and cyclohexane. By evolving an enzyme that could read these funny bases, they were able to read DNA into XNA as well as the reverse. Plus it’s super-strong and resistant to breaking or cleaving.
Molecules like XNA could expand the information code for synthetic biology as well as help us answer the ultimate question about DNA: Why that, and not something else? Ed Yong has more great detail here.
Graphical timeline of the Universe
This more than twenty billion years timeline of our universe shows the best estimates of the occurrence of events since its beginning, up until anticipated events in the near future. Zero of the scale is the present day. A large step on the scale is one billion years, a small step one hundred million years. The past time have a minus sign, e.g. the oldest rock on Earth was formed about four billion years ago and this is marked at -4e+09 years. The “Big Bang” event happened 13.7 billion years ago.
(via jtotheizzoe)
Famous Physicists as Children
From left to right:
Stephen Hawking (b. 1942) - Most well known for Hawking radiation and theorems involving gravitational singularities. He suffers from ALS, also known as Lou Gehrig’s disease - and is one of the most well known scientists of our time.
Neil deGrasse Tyson (b. 1958) - Currently the director of the Hayden Planetarium at the Rose Center for Earth and Space, Tyson is one of the leading science advocates in the world - and was one of the men who supported the demotion of Pluto.
Carl Sagan (1934-1996) - One of the most successful science popularizers of all time, Sagan was also the bestselling author of Cosmos, one of the most popular science books of all time. He was the first to propose that Jupiter’s moons Titan and Europa may hold liquid components of water on them.
Albert Einstein (1879-1955) - The most well known genius in history, Albert Einstein was a boss. During his career, he revolutionized almost every area of Physics, including quantum mechanics and he effectively founded the study of Cosmology. His theory of general relativity has been wildly successful, despite ‘attacks’ by neutrinos.
Richard Feynman (1918-1988) - His most important contributions came via his path integral formulation of quantum mechanics and development of Quantum Electrodynamics (QED). Plus, he was a total badass.
(via freshphotons)
A photoset of smiling owls.
TL, MR, BL - Snowy Owls, TR - Great Horned Owl, ML, BR - Barn Owl
( Visualising Sound ) Waves installation by Daniel Palacios [VIDEO]
“A long piece of rope represents a series of waves floating in space, as well as producing sounds from the physical action of their movement: the rope which creates the volume also creates the sound by cutting through the air.”
(via quippishendeavor)
