An interesting article titled “Symbiotic relationship between Streptococcus mutans and Candida albicans synergizes the virulence of plaque-biofilms in vivo,” appears in the February 2014, edition of Infection and Immunity, written by Megan L. Falsetta and et al.
The article describes how although Streptococcus mutans is often cited as the main bacteria in dental caries (cavities), particularly in early-childhood caries (ECCs), it may not act alone and may team up with Candida albicans. The infection with both can double the number of caries and increase their severity as it did for rats in the study. Candida albicans adheres mainly to the cheek and tongue, while Streptococcus mutans sticks to the surfaces of teeth by converting sugars to a sticky glue-like material called extracellular polysaccharide (EPS).
The researchers found that the exoenzyme that S. mutans uses to react with sugar to produce EPS also enables Candida to produce a glue-like polymer in the presence of sugar, which makes it adhere to teeth and bind S. mutans. It lacks these abilities otherwise. When this occurs the fungus contributes the bulk of the plaque.
The researchers note that the combination of the two organisms led to a enhanced product of the glue-like polymer which boosts the ability of the bacteria and fungus to colonize the teeth while increasing the bulk of biofilms and the density of the infection. This led to an elevated accumulation next to the teeth of the acid that dissolves enamel and additional caries formation.
The observations noted by the researchers supports the hypothesis that ECC in the young results from infection by both organisms. These results can lead to new agents to prevent ECC and hopefully prevent children from acquiring infection.