Found: Gene That Launches Infections

Discovery Could Lead To New Vaccines, Antibiotics

SANTA BARBARA, Calif., Posted 3:55 p.m. May 6, 1999 -- Researchers have isolated a key gene that bacteria use to launch killer infections. The discovery could lead to powerful new vaccines and antibiotics.

Researchers have demonstrated in lab studies that removing or inactivating a gene called DAM can disarm a strain of salmonella. One researcher says it's a "genetic master switch." The researchers say the gene makes a protein that turns on other genes that start the infection.

When strains of salmonella were created with a disabled gene, the microbe could not cause disease in mice. And a researcher says the altered bacteria acted like a vaccine. Mice developed antibodies that would attack salmonella.

A variety of other bacteria, including cholera and plague, also have this type of gene. This raises the possibility that those diseases could also be disabled.

The study at the University of California, Santa Barbara is in the journal Science.

Copyright 1999 by The Associated Press