"As we piece together the family tree for these organisms, we can develop gene probes and ask: 'Who's here? Which dechlorinators are working here?' And that will tell us whether some enhancement would be helpful or whether the problem will take care of itself," Gossett said.

The Cornell researchers have learned enough about Strain 195 to show that the tiny pollution-eater has a limb of its own on the bacterial family tree. Equipped with an unusual cell wall structure that makes it completely resistant to most common antibiotics, Strain 195 may be a unique match for some of the most irreducible compounds that modern chemistry has devised.

"It's as if this bug were born to dechlorinate," Zinder said.

"Then what was it doing before we invented chlorinated ethylenes?" Gossett asked. "It's true, there are some natural levels (of chlorinated ethylenes) in nature, but not in the high concentrations normally needed to support growth."

The evolutionary origin of Strain 195 is just one of the questions on the research agenda for the Cornell microbiologists.

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Contact: Roger Segelken
hrs2@cornell.edu
607-255-9736
Cornell University News Service
5-Jun-1997