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Streptococcus mutans The Principle Investigator on this project is Dr. Joseph Ferretti, Senior Vice President and Provost of OUHSC. Streptococcus mutans is the leading cause of dental caries (tooth decay) worldwide and is considered to be the most cariogenic of all the oral streptococci. The genome of S. mutans UA159, a serotype c strain, has been completely sequenced and is composed of 2,030,936 base pairs. It contains over 1,900 ORFs, approximately two-thirds of which have been assigned putative functions. The genome analysis provides further insight into how S. mutans has adapted to surviving the oral environment through resource acquisition, defense against host factors, and use of gene products that maintain its niche against microbial competitors. S. mutans metabolizes a wide variety of carbohydrates via non-oxidative pathways, and all of these pathways have been identified, along with the associated transport systems whose genes account for almost 15% of the genome. Virulence genes associated with extracellular adherent glucan production, adhesins, acid tolerance, proteases and putative hemolysins have been identified. Strain UA159 is naturally competent and contains all the genes essential for competence and quorum sensing. Mobile genetic elements in the form of IS elements and transposons are prominent in the genome including a novel conjugative transposon and a composite transposon containing genes for the synthesis of antibiotics of the gramicidin/bacitracin family, however no bacteriophage genomes are present. These data were recently published in the Proceedings of the National Academy of Science (Ajdic, D. et al. , "Genome Sequence of Streptococcus mutans UA159, a cariogenic dental pathogen", PNAS (USA) 99 (22): 14,434-9, 2002.). [view PDF]
metabolic pathways
Fig. 2. Reconstruction of specific metabolic pathways and transport mechanisms in S. mutans. Based on the annotated genome sequence, extracellular and intracellular sugar metabolism and metabolism of organic compounds are shown. Transporters are grouped by substrate specificity: red, carbohydrates; green, amino acids/peptides; gold, inorganic cations; blue, inorganic anions; purple, DNA/nucleotides; black, drugs and unclassified. Question marks indicate uncertainty of substrate specificity. Arrows represent the direction of solute transport. Each figure shape represents the specific type of transporter. (see publication for more details).
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circular map
credits The Streptococcus mutans genome sequencing project is a collaboration between Dr. Joseph Ferretti, Ph.D. of the University of Oklahoma Health Sciences Center and Dr. Bruce Roe, Ph.D. of the Advanced Center for Genome Technology. The data for this project is hosted on Dr. Roe's website, and can be found here. (Link will open in a new window)
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