Alteration of the coadherence of Candida albicans with oral bacteria by dietary sugars

Abstract

Interactions between bacterial oral flora and Candida albicans are important in denture plaque formation. This study therefore first aimed to quantify the coadherence of C. albicans and bacteria by the use of a bioluminescent adenosine triphosphate (ATP) assay based on the firefly luciferase-luciferin system. The second aim was to examine the effect of i) dietary sugars (used for preculture) and ii) enzymatic digestion of fungi on the coadherence. When yeast was preincubated in yeast nitrogen base medium (YNB) supplemented with 250 mM glucose, the yeast coadhered with all isolates of Streptoccus mutans and Streptococcus sanguis, and no significant coadhesion was observed with the isolates of Streptococcus sobrinus, Streptococcus salivarius, Lactobacillus and Actinomyces. However, when the yeast was precultured in YNB supplemented with 500 mM galactose, the yeast coadhered with S. salivarius and Actinomyces, which was not observed when the yeast was grown in YNB with glucose. In addition, the coadherence of the yeast with the isolates of S. sanguis was significantly reduced. Enzymatic digestion of yeast and a reverse transcription polymerase chain reaction assay revealed that expression of at least two types of proteinaceous adhesins are involved in these phenomena.

Analysis of the in vitro adherence of Streptococcus mutans and Candida albicans

“…Given that C. albicans has efficient adherence mechanisms, its colonization of the oral environment might represent a predisposing factor favoring its interaction with S. mutans, as has been suggested by several authors (1,23,26,35). Most studies on the in vitro interaction between two microorganisms use either reference strains or isolates from different hosts (6,(24)(25)(26). The use of isolates from hosts colonized by both microorganisms can be a starting point to future findings in specific populations.…”

“…According to Soll (33), C. albicans is capable of differentiation, showing yeast-like and filamentous developmental forms in association with both disease and commensalism, although the yeast-like form is more prevalent in the case of comensalism. Nikawa et al (24) analyzed the coadherence of C. albicans with oral bacteria and also found a predominance of blastospores during the co-adhesion with S. mutans in a culture medium supplemented with sucrose. These authors considered the coaggregation as a key factor in the ecology of oral biofilms.…”

“…Average adherence values were assessed by an analysis of variance (ANOVA) according to a completely randomized design with two replicates and a factorial distribution of the treatments: monospecific culture of clinical isolates and reference strains of S. mutans (M), C. albicans (C) and the combined culture of both species (M+C) and culture times (2,12,24,48, and 72 h). Multiple comparisons were processed using the orthogonal contrasts of the F test according to Hinkelmann and Kempthorne (12).…”

“…A total of 12 acrylic sheets with dimensions 0.5 cm X 2.5 cm X 0.5 mm were placed in individual test tubes containing 0.9 mL of Gibbons and Nygaard culture medium and 0.1 mL of the inoculate. Culture was carried out at 37ºC for different incubation periods (2,12,24,48, and 72 h), with one repetition for each analyzed period.…”

Yeasts in Apical Periodontitis

“…However, it has been reported that C. albicans may prolong the viability of ␤-hemolytic streptococci (Burnet and Sherp, 1968). Furthermore, C. albicans co-aggregates with a variety of streptococci such as S. gordonii, S. mutans, and S. sanguis (Holmes et al, 1995;Nikawa et al, 2001). This may promote their colonization and thus explain the concomitant occurrence of these microbial species.…”