Coaggregation between Streptococcus gordonii PK488 and Actinomyces naeslundii PK606 is mediated by a 38-kDa streptococcal protein, designated ScaA. The gene, scaA, which encodes this protein has been cloned into Escherichia coli. A genomic S. gordonii PK488 library (in Lambda ZAP II) was screened with anti-S. gordonii immunoglobulin G absorbed with S. gordonii PK1804, an isogenic coaggregation-...

Saliva adhesion of bacteria is a key event in oral biofilm formation. Here, we used partial least-squares (PLS) analysis to correlate adhesion of cariogenic (Streptococcus mutans Ingbritt) and commensal (Actinomyces naeslundii LY7) model bacteria, and their agglutinin and acidic proline-rich protein ligands, respectively, with high and low caries experiences in 38 children reflecting today's sk...

A selective medium (CFAT) was developed for the detection and enumeration of Actinomyces viscosus and Actinomyces naeslundii in dental plaque. Neutral acriflavin and potassium tellurite were used in combination with the known selective agents cadmium and fluoride to eliminate most of the competing plaque flora. Composition of CFAT per liter was as follows: Trypticase soy broth (BBL Microbiology...

We present the case of a 77-year-old woman who developed an Actinomyces naeslundii infection of a hip prosthesis. The isolate grew well aerobically with 5% CO(2). Possible diagnostic problems may arise in the microbiological laboratory because aerobic growth is not sufficiently accounted for in some of the traditional identification schemes and commercial test kits. Therefore, besides presentin...

Actinomyces naeslundii and Streptococcus gordonii, oral bacteria that possess Gal/GalNAc- and sialic acid-reactive lectins, respectively, were adherent to immobilized secretory immunoglobulin A (IgA) and two IgA1 myeloma proteins but not to two IgA2 myeloma proteins. Apparently, O-linked oligosaccharides at the hinge region of the IgA1 heavy chain are receptors for lectin-mediated adhesion of t...

An in vitro model of supragingival plaque associated with gingivitis was characterized by traditional culture techniques, comparative 16S rRNA gene sequencing of isolates, and quantitative PCR (QPCR). Actinomyces naeslundii, Prevotella spp., and Porphyromonas gingivalis increased under conditions emulating gingivitis. Gram-negative species and total bacteria were dramatically underestimated by ...