Oral Microbiota Profile Associates with Sugar Intake and Taste Preference Genes

Abstract

Oral microbiota ecology is influenced by environmental and host conditions, but few studies have evaluated associations between untargeted measures of the entire oral microbiome and potentially relevant environmental and host factors. This study aimed to identify salivary microbiota cluster groups using hierarchical cluster analyses (Wards method) based on 16S rRNA gene amplicon sequencing, and identify lifestyle and host factors which were associated with these groups. Group members (n = 175) were distinctly separated by microbiota profiles and differed in reported sucrose intake and allelic variation in the taste-preference-associated genes TAS1R1 (rs731024) and GNAT3 (rs2074673). Groups with higher sucrose intake were either characterized by a wide panel of species or phylotypes with fewer aciduric species, or by a narrower profile that included documented aciduric- and caries-associated species. The inferred functional profiles of the latter type were dominated by metabolic pathways associated with the carbohydrate metabolism with enrichment of glycosidase functions. In conclusion, this study supported in vivo associations between sugar intake and oral microbiota ecology, but it also found evidence for a variable microbiota response to sugar, highlighting the importance of modifying host factors and microbes beyond the commonly targeted acidogenic and acid-tolerant species. The results should be confirmed under controlled settings with comprehensive phenotypic and genotypic data.

Heritability of Oral Microbiota and Immune Responses to Oral Bacteria

“…Understanding the host mechanisms which regulate the oral microbiota composition and function may, therefore, provide novel approaches to treat dental diseases. These mechanisms might involve genetic host regulation of immune response as suggested by the results of the present paper, but also a range of other mechanisms, such as the expression of (glyco) proteins/peptides, which regulate bacteria attachment or metabolism [63] or genetic effects on host behavior such as innate food preferences [15,22,64]. Future studies, including genome-wide host genetic information and oral microbiota data, may help establish these mechanisms.…”

“…The kit used for DNA extraction for the Swedish Twin Registry samples lacked the additional enzymes commonly used to facilitate breakage of the cell walls of more hard-to-break bacteria. To estimate how this would affect the yield, a validation analysis was performed where seven saliva samples and three mock samples of known bacterial species were extracted at the KI Biobank and at our laboratory in Umeå using our routine method, i.e., the GenElute Bacterial Genomic DNA (Sigma-Aldrich, St. Louis, MO, USA) with Proteinase K and RNase and additional lysozyme and mutanolysin [22]. Sequencing was done in two independent runs at the Illumina MiSeq platform as described previously [22] and followed the same bioinformatic process as used for the twin samples.…”

“…Species-level microbial abundance data contain multiple correlated variables organized in a hierarchical cluster pattern [ 22 ]. To account for this when adjusting p -values for multiple testing, the iPVs package ( ) was used to estimate the multiple testing burden.…”

“…A different approach is to assess microbial community functions, i.e., metabolic and other activities. Recent findings indicate that oral microbiotas with different compositions may still have similar functions and represent similar bacterial ecosystems [22]. Hence, estimating bacteria community functions may provide an alternative way to characterize the oral microbiota, which is more biologically and functionally relevant for oral diseases or host interactions such as maturation of immunity.…”

Differences in Sweet Taste Perception and Its Association with the Streptococcus mutans Cariogenic Profile in Preschool Children with Caries

“…The microbiome of the human oral cavity consists of a difficult to determine number of microorganisms representing distinct ecological niches limited anatomically, e.g., microbiota of the surface of the tongue, cheek, teeth, palate, etc. The factors determining the variable composition of oral microbes, apart from the anatomical structure, are: saliva quality, eating habits, and the taste preferences that are the subject of this study [39].…”