Ancient plant compounds discovered in salt walls of waste treatment sites

It has just been discovered that cellulose dating back 253 million years along with some perhaps ancient DNA samples in salt crystals under a ground of nuclear waste in southern Mexico.

According to Jack D. Griffith, a professor of microbiology and immunology at the University of North Carolina School of Medicine, 'We actually detect ancient DNA in salt, but not much and we have to continue testing to make sure it's ancient DNA pattern. ' Cellulose is an organic compound, the main ingredient in the cell walls of green plants and algae.

The compound was found to be locked in transparent salt crystals, turning reddish brown at the government's Waste Separation Plant (WIPP) near Carlsbad.

These crystals were taken from newly exploited areas beneath the desert surface of WIPP about 610m in the fall of last year and about 2 years ago.

'We found in a horizontal wall about 70cm, looking almost like a giant frozen ice. Other parts were found in smaller and finer crystals, mixed with sulfur and clay. '

Griffith argues that finding cellulose in a salt mine could provide a way to search for life on other planets, since this hard compound would be the ideal target for finding ancient signs of life.

He and his colleagues presented their findings in the April issue of the Astrobiology.

Above: Scientists extract salt samples from the walls of the government's nuclear waste treatment plant.
Below: 253 million-year-old salt crystals contain cellulose and may have ancient DNA. (Photo: Jack D. Griffith / UNC-Chapel Hill)

Not fossils

Griffith's group uses small drill bits with a cat whisker to drill into crystals that carry water and collect water droplets.

'These material groups contain saturated saline, which is basically a type of time measuring tool dating back 250 million years.'

The ocean circulation cycle in the Permian period, which lasted about 299 million to 251 million years ago, created salts up to 600m thick and contained waste. Samples of water droplets are placed in centrifuges and sediments from water are examined by electron microscopy.

'We think it is possible to find bacteria or viruses or DNA. But there are these types of fiber materials, which later tests and studies found as cellulose.

The london looks like a very thin network of pasta. These fibers are twice the diameter of a DNA molecule.

According to Karl Niklas, a lecturer in the Department of Plant Biology at Cornell University and not involved in the study, the discovery of cellulose, probably belonging to a type of fibrous algae, is important and interesting.'The cell walls are very well preserved, so Griffith's group has pure cellulose.'

Ancient cellulose did not suffer from fossils - the process by which biological materials were replaced by minerals. The cellulose is ' a fairly simple structure. And it's probably a simple step for the first life forms billions of years ago to start connecting these things together. '

'Groups of bacteria can use it to synthesize carpet forms. They can envelop themselves in there to protect themselves. The cellulose is not only extremely stable but it is also the most abundant molecule on earth. '

Plants, algae and bacteria produce hundreds of billions of tons of cellulose a year. Griffith and students have discussed examining older salt blocks - such as a nearly 400 million-year-old salt mine beneath the Detroit, Michigan area - to find cellulose.