[The effects of lipoteichoic acid and calcium on the adherence of oral streptococci in vitro].

In this study, the effects of lipoteichoic acid (LTA) and calcium on adherence of oral streptococci in vitro were investigated. The results revealed that the adherence of streptococcus sobrinus to a glass surface was increased by the addition of calcium, in the condition of the same calcium ion concentration, LTA inhibited adherence, suggesting that LTA and the bacterial cell surface LTA competed for the same site of calcium ion, providing some evidence to support calcium-bridging theory. The result also showed that calcium ion not only influenced sucrose-independent adherence, but also infulenced sucrose-dependent adherence. The effect of calcium ion on the adherence has a threshold, over which the adherence was reduced.