In 2004 a spacecraft already on its way to Saturn will drop a probe onto Titan, a moon with a dense atmosphere of nitrogen - an ingredient for life as we know it. Another mission, the Titan Biologic Explorer is already on the drawing boards. Sampling missions are also scheduled to land on passing comets to see if they really are the water carriers of the solar system, as some scientists suspect. Almost all the missions in space for the next decade seem aimed at finding evidence of life out there. While probes look for extraterrestrial life, Earth-bound biologists will push harder to understand what life is and how it comes to be.
Humans now have the potential to direct life beyond Earth.
The enzyme, called DGAT, joins with other molecules to produce a specific group of fats called triglycerides, which make up more than 95 percent of fatty tissue in humans. Robert Farese, Jr., the principal investigator at Gladstone in San Francisco, said researchers have known about DGAT for several decades but have until now been unable to isolate the elusive enzyme. Farese said the finding also could have applications in agriculture because DGAT plays an important role in the synthesis of seed oils, such as canola oil, in plants. Farese and his fellow researchers were able to isolate the tricky enzyme by using a kind of genetic fingerprinting. The group had been studying a related enzyme called ACAT, which is involved in cholesterol metabolism.