B3: The vitamin from outer space

Vitamin B3, also called nicotinic acid or niacin, is the precursor to nicotinamide adenine dinucleotide (NAD) -- vital to metabolism and a key to the development of ancient life. And though its possible B3 developed non-biologically on ancient Earth, scientists say it's likely carbon-rich meteorites peppering the planet millions of years ago offered an extra dose of niacin. In studying an array of meteorite samples, scientists at Goddard's Astrobiology Analytical Laboratory found vitamin B3 at levels ranging from about 30 to 600 parts per billion, proof the essential compound is produced naturally somewhere in outer space. "We discovered a pattern -- less vitamin B3 (and other pyridine carboxylic acids) was found in meteorites that came from asteroids that were more altered by liquid water," explained Karen Smith of Pennsylvania State University, who helped lead the study. "One possibility may be that these molecules were destroyed during the prolonged contact with liquid water," added Smith. "We also performed preliminary laboratory experiments simulating conditions in interstellar space and showed that the synthesis of vitamin B3 and other pyridine carboxylic acids might be possible on ice grains." The natural followup question: are meteorites rich in B3 proof of extraterrestrial life? Smith and her colleagues don't think so. The nicotinic acid found in these carbon-rich celestial rocks came attached to molecules not used to create life. While the randomness of non-biological chemistry tends to result in a full array of molecular products -- life makes only the molecules it needs, nothing more.