Comparison of the genome of the oral pathogen Treponema denticola with other spirochete genomes

doi:10.1073/pnas.0307639101

Comparison of the genome of the oral pathogen Treponema denticola with other spirochete genomes

^*The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, MD 20850; ^†Johns Hopkins University, Charles and 34th Streets, Baltimore, MD 21218; ^∥Departments of Pharmacology and Microbiology and Tropical Medicine, The George Washington University School of Medicine, 2300 Eye Street Northwest, Washington, DC 20037; ^‡Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, MD 21202; ^¶Department of Pathology and Laboratory Medicine and Graduate School of Biomedical Sciences, University of Texas Health Science Center, 6431 Fannin Street, Houston, TX 77230; and ^§Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030

Edited by Robert Haselkorn, University of Chicago, Chicago, IL, and approved February 9, 2004 (received for review November 20, 2003)

Abstract

We present the complete 2,843,201-bp genome sequence of Treponema denticola (ATCC 35405) an oral spirochete associated with periodontal disease. Analysis of the T. denticola genome reveals factors mediating coaggregation, cell signaling, stress protection, and other competitive and cooperative measures, consistent with its pathogenic nature and lifestyle within the mixed-species environment of subgingival dental plaque. Comparisons with previously sequenced spirochete genomes revealed specific factors contributing to differences and similarities in spirochete physiology as well as pathogenic potential. The T. denticola genome is considerably larger in size than the genome of the related syphilis-causing spirochete Treponema pallidum. The differences in gene content appear to be attributable to a combination of three phenomena: genome reduction, lineage-specific expansions, and horizontal gene transfer. Genes lost due to reductive evolution appear to be largely involved in metabolism and transport, whereas some of the genes that have arisen due to lineage-specific expansions are implicated in various pathogenic interactions, and genes acquired via horizontal gene transfer are largely phage-related or of unknown function.

Footnotes

↵ ** To whom correspondence should be addressed. E-mail: ipaulsen{at}tigr.org.
This paper was submitted directly (Track II) to the PNAS office.
Abbreviation: CDS, protein-coding sequences.
Data deposition: The sequence reported in this paper has been deposited in the GenBank database (accession no. AE017226).