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Researchers create ‘artificial life’
Researchers at Rockefeller University in the US have made the first tentative steps towards creating a form of artificial life.
Their creations, small synthetic vesicles that can process (express) genes, resemble a crude kind of biological cell.
The parts for their “vesicle bioreactors”, as they call them, all come from diverse realms of life.
The soft cell walls are made of fat molecules taken from egg white. The cell contents are an extract of the common gut bug E.coli, stripped of all its genetic material.
This essence of life contains ready-made much of the biological machinery needed to make proteins; the researchers also added an enzyme from a virus to allow the vesicle to translate DNA code.
When they added genes, the cell fluid started to make proteins, just like a normal cell would.
A gene for green fluorescent protein taken from a species of jellyfish was the first they tried. The glow from the protein showed that the genes were being transcribed.
With a second gene, from the bacterium Staphylococcus aureus, the researchers got their cells to make small pores in their walls.
Some bacteria can survive with just a few hundred genes
These let nutrients in from the surrounding “soup,” so that the cells could function, in some instances, for several days.
Albert Libchaber, who heads the project, stresses that these bioreactors are not alive — they’re performing simple chemical reactions that can also happen in cell-free biological fluids.
Climate talks end
UN talks on climate change ended last weekend in Buenos Aires with few steps forward as the United States, oil producers and developing giants slammed the brakes on the European Union’s drive for deeper emissions cuts to stop global warming.
Although negotiators brokered an eleventh-hour agreement on two items, EU made it clear that the deal fell short of its goal to get talks rolling for after 2012, when the Kyoto protocol to cut greenhouse gases runs out. “A lot of people are afraid of discussing the future,” said EU head delegate Pieter van Geel, the Dutch environment secretary.
The meeting of nearly 200 nations and 6,000 participants started on a high note 12 days ago after Russia’s ratification of the Kyoto protocol last month, allowing the treaty to take effect in February with a seven-year delay.
Kyoto will cut emissions in industrialized countries by 5 per cent from 1990 levels, a first small step. EU believes it will have to reduce its emissions by at least half by mid-century and mandatory cuts are the preferred method.
EU came to Buenos Aires wanting to narrow differences with the United States, the source of 25 per cent of the world’s heat-trapping gases, and the large developing economies excluded from Kyoto like China and India.
But it soon became clear that Washington was sticking to its 2001 decision to bow out of Kyoto for fear of the impact that mandatory emissions curbs would have on economic growth.
Titan clouds
Scientists now have first direct evidence of changing weather patterns on Titan, Saturn’s largest moon. When the Cassini spacecraft flew past the satellite on Monday it spied clouds at mid-latitudes that were not present on its last flyby in October.
The observations will allow researchers to investigate atmospheric dynamics on Titan, the only moon in the Solar System with a thick covering of gas.
The results came out at the American Geophysical Union’s (AGU) fall meeting. Cassini also saw banding and layering in the moon’s upper atmosphere.
In addition, mission scientists took the opportunity at the meeting to share images of Dione, one of Saturn’s smaller icy moons, which Cassini passed at a distance of 81,400km on early last week.
World nears flu pandemic
Health officials in Singapore warned that the world was close to its next pandemic — a powerful and highly contagious mix of avian influenza and flu virus that would likely be centered in Asia. Authorities also warned that humans, and not animals as initially thought, would probably be the carriers.
“We are getting closer, but when it’s going to happen, I don’t know,” said Francois Xavier-Meslin, Who’s coordinator for disease control, prevention and eradication.
“If it happens, which is not yet proven, it’s going to be worse than SARS,” he said at a task force meeting on bird flu led by the Association of Southeast Asian Nations.
The H5N1 bird flu virus killed 32 people in Thailand and Vietnam this year, while SARS — Severe Acute Respiratory Syndrome — killed 774 and infected nearly 8,000, mostly in Asia, in 2003. Both outbreaks caused widespread economic losses throughout the region.
Ozone hole pulls back
The ozone hole has pulled back once more to Antarctica this spring, leaving behind a shadow of uncertainty for the people living at the bottom of the Americas.
The people of Punta Arenas are adjusting to the intense radiation that pours each year through the gap in the ozone layer. “People are better informed. They’re buying more sun-block and putting it on their children,” said pharmacist Gerardo Leal.
The stratosphere’s layer of ozone, a form of oxygen, filtered out almost all the sun’s cancer-causing ultraviolet-B rays. But in the 1970s scientists warned that manmade chemicals such as chlorofluorocarbons (CFCs), used in aerosol sprays and refrigerants, were destroying ozone through chain reactions high in the skies. — Sci-tech World Report
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