Abstract
The short-term kinetics of fluoride uptake by cells from 20- to 22-h cultures of S. mutans strain 6715 were studied using rapid filtration and centrifugation techniques. Saline-suspended organisms were diluted with fluoridecontaining solutions buffered at four different pH values (2.0, 4.0, 5.5, and 8.2). Fluoride disappearance from the medium was inversely related to pH and to the duration of the exposure at any given pH. The uptake was rapid and extensive at the lower pH values and decreased as the pH increased. Media fluoride concentrations subsequently increased; i.e., fluoride was released from the cells. The presence of glucose, cyanide, or iodoacetate did not influence the results. However, preincubation of the cells in fluoride-free buffers, followed by the addition of fluoride, reduced fluoride uptake markedly. Cell-to-media pH gradients were determined by the distribution of 14C-labeled 5,5-dimethyl-2,4-oxazolidinedione. Fluoride uptake was found to be a function of the magnitude of the pH gradient (P < 0.001). It is hypothesized that fluoride uptake occurs by the diffusion of hydrogen fluoride and the subsequent trapping of ionic fluoride.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 680-687 |
| Number of pages | 8 |
| Journal | Infection and Immunity |
| Volume | 18 |
| Issue number | 3 |
| State | Published - Dec 1 1977 |
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ASJC Scopus subject areas
- Parasitology
- Microbiology
- Immunology
- Infectious Diseases
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Fluoride uptake by Streptococcus mutans 6715. / Whitford, G. M.; Schuster, G. S.; Pashley, D. H.; Venkateswarlu, P.
In: Infection and Immunity, Vol. 18, No. 3, 01.12.1977, p. 680-687.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Fluoride uptake by Streptococcus mutans 6715
AU - Whitford, G. M.
AU - Schuster, G. S.
AU - Pashley, D. H.
AU - Venkateswarlu, P.
PY - 1977/12/1
Y1 - 1977/12/1
N2 - The short-term kinetics of fluoride uptake by cells from 20- to 22-h cultures of S. mutans strain 6715 were studied using rapid filtration and centrifugation techniques. Saline-suspended organisms were diluted with fluoridecontaining solutions buffered at four different pH values (2.0, 4.0, 5.5, and 8.2). Fluoride disappearance from the medium was inversely related to pH and to the duration of the exposure at any given pH. The uptake was rapid and extensive at the lower pH values and decreased as the pH increased. Media fluoride concentrations subsequently increased; i.e., fluoride was released from the cells. The presence of glucose, cyanide, or iodoacetate did not influence the results. However, preincubation of the cells in fluoride-free buffers, followed by the addition of fluoride, reduced fluoride uptake markedly. Cell-to-media pH gradients were determined by the distribution of 14C-labeled 5,5-dimethyl-2,4-oxazolidinedione. Fluoride uptake was found to be a function of the magnitude of the pH gradient (P < 0.001). It is hypothesized that fluoride uptake occurs by the diffusion of hydrogen fluoride and the subsequent trapping of ionic fluoride.
AB - The short-term kinetics of fluoride uptake by cells from 20- to 22-h cultures of S. mutans strain 6715 were studied using rapid filtration and centrifugation techniques. Saline-suspended organisms were diluted with fluoridecontaining solutions buffered at four different pH values (2.0, 4.0, 5.5, and 8.2). Fluoride disappearance from the medium was inversely related to pH and to the duration of the exposure at any given pH. The uptake was rapid and extensive at the lower pH values and decreased as the pH increased. Media fluoride concentrations subsequently increased; i.e., fluoride was released from the cells. The presence of glucose, cyanide, or iodoacetate did not influence the results. However, preincubation of the cells in fluoride-free buffers, followed by the addition of fluoride, reduced fluoride uptake markedly. Cell-to-media pH gradients were determined by the distribution of 14C-labeled 5,5-dimethyl-2,4-oxazolidinedione. Fluoride uptake was found to be a function of the magnitude of the pH gradient (P < 0.001). It is hypothesized that fluoride uptake occurs by the diffusion of hydrogen fluoride and the subsequent trapping of ionic fluoride.
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M3 - Article
C2 - 22490
AN - SCOPUS:0017751626
VL - 18
SP - 680
EP - 687
JO - Infection and Immunity
JF - Infection and Immunity
SN - 0019-9567
IS - 3
ER -