Major Differences Found Between Genomes Of Oral Pathogen And Related Spiral-shaped Bacteria That Cause Syphilis And Lyme Disease

Three centuries after a pioneering Dutch microbiologist first observed the spiral-shaped oral pathogen Treponema denticola, scientists have deciphered the bacterium’s entire DNA sequence and used comparative genomics to cast new light on other spirochete microbes. The study by scientists at The Institute for Genomic Research (TIGR) and collaborators at Baylor College of Medicine and the University of Texas Health Science Center at Houston found profound differences between the gene content of T. denticola, which is associated with periodontal (gum) disease, and of other spirochetes that cause syphilis and Lyme disease. “This highlights the power of comparative genomics to help us understand how related pathogens can cause completely different diseases,” says Ian Paulsen, who led the sequencing along with fellow TIGR researcher Rekha Seshadri. Paulsen says the T. denticola genome “provides an excellent point of reference to study the biology of spirochetes.” The paper will appear in the April 13, 2004 issue of Proceedings of the National Academy of Sciences (PNAS) and was scheduled to be published online this week. The study was supported by the National Institute of Dental and Craniofacial Research (NIDCR), which is part of the U.S. National Institutes of Health.