DNA Nanovases

Nanotechnologists from Arizona State University, USA have made "bowls", "flasks" and "vases" of nano-dimensions with nothing but DNA. This they have achieved using DNA Origami, a self-assembly technique where strands of DNA are folded and "stapled" together to make intricate structures just as paper is used in the conventional origami.

DNA Crystallization in vivo

Bacteria are some of the marvelous creations of nature. They are known for their adaptability. The humble Escherichia coli that we find in almost all the microbiology and molecular biology labs continues to surprise us with its ingenius ways of handling problems.

Under extreme stress, bacterial cells are known to take many steps to protect themselves. Abraham Minsky of the Weizmann Institute of Science in Rehovot, Israel identified an interesting defense mechanism of E.coli thats slightly different. These unicellular organisms crystallize their own DNA.
This 'novel' defence strategy was found to be the responsibility of a protein called Dps. It resembles ferritin, an iron-storage protein found in humans.

Dps is produced when the cell experiences nutritive or oxidative stress. It binds to DNA (apparently without any specificity) and promotes its crystallisation. Earlier investigations revealed another important function of the Dps protein. It sequesters iron and other metal ions that may help in the generation of free-radicals.


DNA - Dps crystals

Minsky and his collegues genetically engineered a few bacterial cells to over-produce this protein. These cells formed DNA crystals more easily and starvation was sufficient to cause crystallization of DNA. This process was also found to be reversible. "Once nutrients are supplied, [the crystals] disappear within a very short timescale, and the bacteria are viable and growing," says Minsky.

Whats remains to be explained is, how the bacterial DNA integrates itself into a crystal!

The DNA message

You probably know that DNA carries the most invaluable information, without which the mere existence of life is impossible. Have you ever wondered whether DNA can be used to store more than just the genetic information? If you had thought of it before, you are not alone(!!!!!!).

A group of Japanese Molecular Biologists in Institute for Advanced Biosciences at Keio University decided to (nearly) immortalize Albert Einstein's magical formula E=mc^2 in the DNA of a bacterium.

DNA is a thread like molecule made of 4 different compounds (represented as A, G, C and T) as building blocks. The sequence of these 4 compounds in the DNA holds the genetic information. The Japanese scientists attempted to translate the formula (along with the year of its discovery, "1905") into binary code. This code was then translated into a language that has A, G, C and T as its 4 alphabets. For example, the binary code '0000' was translated into 'AA' and '0001' was indicated as 'CA'. Once the formula was translated into DNA's language (A,G, C and T), the new sequence obtained was inserted into a bacterial DNA and stored for eternity.

The objective here, was probably to preserve 'the most important formula of 21st century'. Since the genetic information had survived for over 3.5 billion years, DNA was the obvious choice. With the ability to survive in extremely hostile environmental conditions, the harmless soil bacterium Bacillus subtilis was a suitable candidate as the carrier of the "DNA-time capsule".

I hope that these efforts prove successful and Einstein's legacy (E=mc^2) lives on long after the demise of human kind on this planet.

Hmmmm....... I wonder what role the seemingly harmless equation E=mc^2 will play in the extinction of human population!

If there is something in this world that never ceases to fascinate me is DNA. Especially, the fact that 6 ft of DNA is coiled into a compartment thats less than 3micrometre diameter. I found this amazing video on youtube. Enjoy!!!!!!