Surface display of proteins by sortases in Gram-positive bacteria is crucial for bacterial fitness and virulence. We found a unique gene locus encoding an amylase-binding adhesin AbpA and a sortase B in oral streptococci. AbpA possesses a new distinct C-terminal cell wall sorting signal. We demonstrated that this C-terminal motif is required for anchoring AbpA to cell wall. In vitro and in vivo...

Treatment of acute streptrococcal sore throat is advocated to hasten clinical resolution, prevent suppurative sequelae and decrease the incidence of rheumatic fever and glomerulonephritis. A 10-day course of penicillin is the standard treatment recommended for Group A beta hemolytic streptococci (GABHS) infection. Many antibiotics, including other beta lactams, macrolides, and clindamycin are a...

The purpose of this study was to investigate the relationship between the number of missing teeth (MT) and the statuses of oral environmental factors (the stimulated salivary flow rate, buffering capacity, and the counts of mutans streptococci, lactobacilli, and Candida) in the elderly. The subjects were 64 elderly subjects with fixed prostheses and 49 who wore removable partial dentures aged o...

Streptococci and veillonellae occur in mixed-species colonies during formation of early dental plaque. One factor hypothesized to be important in assembly of these initial communities is coaggregation (cell-cell recognition by genetically distinct bacteria). Intrageneric coaggregation of streptococci occurs when a lectin-like adhesin on one streptococcal species recognizes a receptor polysaccha...

gingivitis is an inflammatory destructive disease mainly caused by microbial plaques. gram-positive and gram-negative bacilli or cocci have been isolated from dental plaque and gingivitis. this study was going to isolate and characterize the pathogenic bacteria from gingival of 100 patients with oral gingivitis. enriched and specific media used for isolation of bacteria. identification of isola...

Early childhood caries affects 28% of children aged 2-6 in the US and is not decreasing. There is a well-recognized need to identify susceptible children at birth. Caries-free adults neutralize bacterial acids in dental biofilms better than adults with severe caries. Saliva contains acidic and basic proline-rich proteins (PRPs) which attach to oral streptococci. The PRPs are encoded within a sm...

The purpose of the present study was to determine the antibacterial activity of oolong tea extract on oral streptococci, including Streptococcus mutans and Streptococcus sobrinus, and to identify the response to its components. Antibacterial activity was found when the extract was added to S. mutans cells in chemically defined medium but not in complex broth media. Further, pretreatment with bo...

An oral infectious disease, dental caries, is caused by the cariogenic streptococci Streptococcus mutans. The expected preventive efficiency for prophylactics against dental caries is not yet completely observed. Nisin, a bacteriocin, has been demonstrated to be microbicidal against S. mutans, and liposome-encapsulated nisin improves preventive features that may be exploited for human oral heal...

In a quantitative bacteriological study of the salivary flora from 50 children the following aerobic organisms were identified and enumerated: alpha-haemolytic streptococci, beta-haemolytic streptococci, Streptococcus faecalis, pneumococci, Staphylococcus aureus, Staph. albus and Staph. citreus, Neisseria spp, N. meningitidis, corynebacteria, aerobic lactobacilli, B. subtilis, H. influenzae, co...

SpaP is a 1500-residue adhesin expressed on the surface of the caries-implicated bacterium Streptococcus mutans. SpaP is a member of the antigen I/II (AgI/II) family of proteins expressed by oral streptococci. These surface proteins are crucial for the incorporation of streptococci into dental plaque. The structure of the C-terminal domain of SpaP (residues 1136-1489) was solved and refined to ...