Molecular Genetic Analysis of the Virulence of Oral Bacterial Pathogens: An Historical Perspective

Abstract

Applying the then-available technology, investigators suggested the important role of sucrose in the cariogenic properties of S. mutans (Loesche, 1986). These organisms were demonstrated to metabolize sucrose, as well as other sugars, rapidly to lactic acid and to convert a portion of the dietary disaccharide to glucan and fructan polymers. Several laboratories purified and characterized the enzymes involved in the synthesis of these polysaccharides (Mooser, 1992). One of the earliest genetic approaches to characterization of the virulence of an oral pathogen was the demonstration, by Tanzer and colleagues (Freedman et al., 1981), that spontaneous or chemically induced MOLECULAR GENETIC ANALYSIS OF THE VIRULENCE OF ORAL BACTERIAL PATHOGENS: AN HISTORICAL PERSPECTIVE Howard K. KuramitsuDepartments of Oral Biology and Microbiology, State University of New York, Buffalo, NY 14214; kuramits@buffalo.edu ABSTRACT: This review will focus on the impact of molecular genetic approaches on elucidating the bacterial etiology of oral diseases from an historical perspective. Relevant results from the pre-and post-recombinant DNA periods will be highlighted, including the roles of gene cloning, mutagenesis, and nucleotide sequencing in this area of research. Finally, the impact of whole-genome sequencing on deciphering the virulence mechanisms of oral pathogens, along with new approaches to control these organisms, will be discussed.

Extracellular Polysaccharides Matrix — An Often Forgotten Virulence Factor in Oral Biofilm Research

“…mutans is a key contributor to the formation of exopolysaccharide-matrix in dental biofilms. This bacterium produces three Gtfs, products of gtfB, gtfC and gtfD genes (Kuramitsu, 2003): GtfB, which synthesizes mostly insoluble glucans containing elevated amounts of α1,3-linked glucose; GtfC, which synthesizes a mixture of insoluble and soluble glucans [rich in α(1,6) linkages]; and GtfD which synthesizes predominantly soluble glucans. In addition, S. mutans produces a Ftfs, the product of single ftf gene, which catalyzes the synthesis of fructans composed primarily of β(2,1) linkages.…”

Omega-3 Fatty Acid Effect on Alveolar Bone Loss in Rats

“…P. gingivalis is a major pathogen in severe forms of human periodontal disease, and possesses multiple metabolic properties and virulence factors consistent with its pathogenic role in the disease (Kuramitsu, 2003;Holt and Ebersole, 2005). Nevertheless, in vivo studies are considered as crucial steps in documenting specific bacterial pathogenesis.…”

Rat Model of Polymicrobial Infection, Immunity, and Alveolar Bone Resorption in Periodontal Disease

“…While periodontal diseases are polymicrobial and reflect sequential colonization by a broad array of bacteria in the transition from a healthy subgingival biofilm to a diseased subgingival biofilm (5,25,30,40,41), the molecular mechanisms and synergism among the genera and species in the disease are not well understood. Three of the periodontal pathogens, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, are commonly coisolated or identified in subgingival biofilm samples from adult periodontitis lesions (11,40,41).…”