The Associated Press
OKLAHOMA CITY - Scientists have cracked the genetic code for the bacteria that cause strep throat, rheumatic fever and a flesh-eating disease, raising hopes of better treatments for such illnesses.
"We've got the complete dictionary on this bug," University of Oklahoma microbiologist Joseph Ferretti said. "That's really exciting. Now that we know some of its secrets, we can find a way to combat it."
The genetic sequence was published yesterday in the Proceedings of the National Academy of Sciences and is online for scientists around the world.
Ferretti said penicillin is a strong treatment for illnesses caused by Streptococcus pyogenes, but he hopes researchers can develop new antibiotics and vaccinations now that the germ's complete DNA sequence has been determined. There are no proven vaccines to prevent Streptococcus infections, Ferretti said.
Ferretti headed the five-year mapping project, funded by the National Institute of Allergy and Infectious Disease.
Dr. Richard Facklam, chief of the Streptococcus laboratory at the Centers for Disease Control and Prevention, said it remains unclear whether better treatments can be developed for Streptococcus illnesses. But he said the mapping project will speed up the time it takes to determine that.
"Now we can knock out a specific gene and find out in animal studies if it would cause the same type of diseases that it does without the gene," Facklam said.
Researchers obtained a strain of the germ through a wound on a patient who had a serious infection. They grew the strain, isolated its DNA, then used computers to sequence the genetic code.
The bacteria cause thousands of human illnesses each year, including strep throat, impetigo, pneumonia, toxic shock syndrome, blood poisoning, scarlet fever, rheumatic fever and a flesh-eating disease called necrotizing fasciitis.
Millions of cases of strep throat and impetigo occur each year in the United States. Of the 10,000 cases of flesh-eating disease in the United States last year, 13 percent resulted in death, Ferretti said. And rheumatic fever is the major cause of acquired heart disease in children living in developing nations.
During the study, researchers discovered six toxins caused by Streptococcus that were previously unknown. They also gained a better understanding of how toxins travel through the body.