Grab a toothbrush and read on. Gum disease, which afflicts more than 35 million people in the United States, can make teeth fall out if left untreated. Now scientists have released the complete genomic sequence of Porphyromonas gingivalis, one of the bacteria to blame. The sequence is expected to speed up the fight against gum disease as well as other conditions caused by related bacteria.
Gum disease starts when P. gingivalis, with two other conspiring bacterial species, invades the space between the gums and teeth. The infection triggers gum inflammation and, in advanced cases, bone deterioration and tooth loss. Patients with gum disease are usually treated with an uncomfortable deep cleaning to remove the bacteria. In an effort to identify new drug targets, researchers are dissecting the genes that make P. gingivalis so destructive.
To aid that work, scientists led by Robert Fleischmann at the Institute for Genomic Research in Rockville, Maryland, have released the sequence of all 2.3 million base pairs of the P. gingivalis genome (see link below). The release includes a preliminary analysis of the genome's roughly 2200 genes. The genome has already yielded some important information. For instance, the bug apparently uses amino acids, rather than sugars, as a carbon source. That meshes with the fact that P. gingivalis is chock-full of protein-clipping enzymes that scientists think cause the inflammation.
In addition to the distinction of being the first oral pathogen to be sequenced, P. gingivalis has also provided the first genome from the so-called bacteriodes bacteria. That group includes bugs that cause a variety of problems in the digestive system, such as infections after surgery.
The P. gingivalis sequence "is a godsend," says microbiologist Howard Kuramitsu of the State University of New York, Buffalo. Having the sequence will "save months of work" in isolating virulence genes, he adds.