Iodophilic polysaccharide synthesis, acid production and growth in oral streptococci

Abstract

Sammary--The relation between iodophilic polysaccharide formation, acid production and growth in a-haemolytic streptococci, isolated from human dental plaque, was studied. In experiments with resting cell suspensions, or with cells growing at a low rate, all strains synthesizing iodophilic polysaccharide were found to be more acidogenic than strains not producing iodophilic polysaccharide. The higher acid production rate of the iodophilic polysaccharide-producing strains seems to be the result of their increased demand for energy required for polysaccharide synthesis. In cultures of iodophilic polysaccharide-storing strains, with a high initial cell concentration (4-10 l° cells]ml), cell multiplication was delayed and did not occur before the polysaccharide content of the cells was at or near its maximal level. No such delay was observed in cultures of strains not producing iodophilic polysaccharide. With regard to the importance of iodophilic polysaccharide synthesis for the carious process, the acid production from polysaccharide degradation has, up till now, been stressed. The present results indicate that in addition to this process, also the high acid production rate of iodophilic polysaccharide-storing streptococci during polysaccharide synthesis, may increase the acidogenic potential of dental plaques containing such organisms.

The ADP‐glucose pyrophosphorylase from Streptococcus mutans provides evidence for the regulation of polysaccharide biosynthesis in Firmicutes

“…Results obtained for S. mutans ADP-Glc PPase also could be analysed concerning the intracellular metabolic scenario (Fig. 9), since there is an important background regarding sugar utilization and IPS synthesis in oral streptococci (Gibbons and Kapsimalis, 1963;Gibbons, 1964;van Houte et al, 1969;van Houte and Saxton, 1971;Freedman and Coykendall, 1975;Huis in 't Veld and Backer Dirks, 1978;Birkhed and Tanzer, 1979;Takahashi et al, 1991;Spatafora et al, 1999;Takahashi and Nyvad, Fig. 8.…”

Dental Caries

“…This may be especially relevant at night when the fl ow of buffering saliva is greatly diminished. Bacteria which synthesize glycogen also ferment exogenous carbohydrates at a higher rate in vitro, presumably because A TP generated from glycolysis is required for glycogen synthe sis (26). The proportions of bacteria which synthesize large quantities of intracellu lar glycogen are increased on the teeth of individuals with high dental caries activity (27)(28)(29).…”

Effects of Fluoride, Lithium, and Strontium on Intracellular Polysaccharide Accumulation in S. mutans and A. viscosus

“…Intracellular polysaccharides (IPS) are synthesized and stored by some species of plaque bacteria (Berman and Gibbons, 1966;Gibbons and Socransky, 1962;van Houte et a., 1969 and. The ability of the human oral flora to form IPS appears to increase with dietary carbohydrate consumption and caries activity (Loesche and Henry, 1967;deStoppelaar et al, 1970;van Houte, 1964).…”