Title: 0589 - Binding of Streptococcus mutans to Collagen in Presence of Nicotine
Naif Abogazalah (Presenter)
King Khalid University College of Dentistry
George Eckert, Indiana University School of Medicine
Richard Gregory, Indiana University
Objectives: To evaluate the binding capacity of four different strains of stereotype c Streptococcus mutans (SM) exhibiting different expressions of cbm and cnm surface collagen binding proteins, including: SMUA159 (cbm- and cnm-), SM8 (cbm-), SM17 (cnm-), and SM18 (cbm+ and cnm+) strains.
Methods: SM stereotype c strains UA159, SM8, SM17 and SM18 were grown in Tryptic Soy broth (TSB) and cultured in 40 ml of TSB containing 0, 0.5, and 2.0 mg/ml nicotine. Cells were fixed with 0.5% formaldehyde, washed and suspended in saline. The absorbance was standardized using a spectrophotometer at 595 nm. 200 ul of the standardized bacteria were plated in 96 well microtiter plates, washed with tween saline (TS), blocked with 1% bovine serum albumin, washed with TS and 10 μg/ml of collagen type I added. Wells were washed with high salt TS and 1:500 anti-collagen antibody added, followed by 1:500 of absorbed anti-rabbit IgG antibody and washed with high salt TS. O-phenylenediamine was added and the plates incubated at room temperature for 1 hour to allow for color change. The optical density was measured at 490 nm using a spectrophotometer. The control group received the same treatment except anti-collagen. Mixed-model ANOVA analysis was performed and a 5% significance level was used for all tests.
Results: All SM groups at all nicotine concentrations were significantly higher than the no anti-collagen control. Collagen binding increased with nicotine concentration for SMUA159. No differences were observed among nicotine concentrations for SM8, SM17, and SM18. However, without nicotine, SM8 and SMUA159 had significantly higher (p<0.05) collagen binding than SM17and SM18, but no significant differences were found between SM8 and SMUA159 or between SM17 and SM18.
Conclusions: The results illustrate that different SM serotype c strains can bind collagen. Furthermore, SMUA159 binding to collagen increases as nicotine concentration increases.
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE