Born-Again Bacteria

Talk about indirect: to bring dinosaurs back to life, the "scientists" of "Jurassic Park" had to extract dine DNA from the amber it had been embalmed in for millions of years, augment it with frog DNA, slip it into a crocodile egg and wait for the baby beast to hatch. Raul Cane skipped the preliminaries. In the current issue of the journal Science, the California Polytechnic State University microbiologist announces that he has brought a creature entombed in amber back to life. Directly. True, it's only a bacterium, not a Ford-crunching tyrannosaur. But if Cane has done what he says other biologists have serious doubts -- it will be the first time an organism preserved in amber has ever been resurrected. It will also be the oldest organism ever revived from the state of suspended animation known as a spore. Why bother? Cane believes the born-again bugs will produce new antibiotics. The idea is "to tap into an unexplored universe of molecular diversity" to discover new drugs, says Robin Steele of Ambergene Corp., a biotech firm that funded Cano's work.

In 1992 Cane began trying to awaken spores found in the guts of extinct bees, 25 million to 40 million years old. A spore is a form of just-barely life in which there is no metabolism, no DNA activity, no respiration; the oldest spore ever revived was 70 years old. Getting nowhere fast, last September Cane called in specialists on ancient climates: re-creating the warmth and acidity of 25 million years ago might wake up the bacteria. It did. Now Cane reports he's isolated 100-plus Bacillus bacteria from the bees.

Has he really found old bugs--or just modern-day bacteria hanging around his lab? Cane used clean-room technology and sterilized the amber (fossilized tree sap) to prevent contamination by modern bacteria. Also, he reports that the revived bacteria have sequences of DNA different from today's microbes. "He has demonstrated beyond a reasonable doubt that these are 25 million-year-old bacteria," says microbiologist Philipp Gerhardt of Michigan State University.

Other biologists aren't betting on it. "You can't sequence every strain of contemporary bacteria to rule out contamination," says biochemist Peter Setlow of the University of Connecticut Health Center. One possibility, notes molecular biologist Richard Losick of Harvard University, is that "this [revived] spore wasn't really sitting in the amber for 25 million years, but seeped in through a microcrevice a few years ago." But the rumor mill is abuzz with Cano's claim to have isolated not just the spores but 1,500 nonspore bacteria, fungi and yeasts. too. "We have gone well beyond what's in the paper," Cano told NEWSWEEK. Because reviving anything but spores has never been done, Cano's assertion leads scientists to suspect that the original claim will turn out to be untrue.

Ambergene hopes the ancient bacteria could yield antibiotics lethal to today's germs, many of which are resistant to contemporary drugs. The revived microbes have virtually no chance of running amok as bio-weapons: they live in bees and special lab cultures. (Still, Cano has them under lock and key.) Ambergene won't have an Andromeda strain on its hands, but it's probably a long way from having a gold bug.

Bacteria that have been in a deep sleep for 25 million years don't awaken easily. How scientists claim to wake them:

Biologists sterilize the amber that holds the bee. With a thin needle, bacillus spores are extracted from the bee's gut.

Spores are placed in a nutrient solution, at a temperature and acidity similar to those of 25 million years ago.

The born-again bacteria grow and multiply. They produce metabolic products that may be lethal to modern bacteria.

Scientists collect these metabolic products and test them for antibiotic activity. A biotech firm hopes the ancient antibiotics will kill disease-causing bacteria that are resistant modern drugs.