Oral microbiome metabolism: From who are they? to what are they doing?

Recent advances in molecular biology have facilitated analyses of the oral microbiome (who are they?); however,its functions (e.g.,metabolic activities) are poorly understood (what are they doing?). this review aims to summarize our current understanding of the metabolism of the oral microbiome. saccharolytic bacteria - including streptococcus,actinomyces,and lactobacillus species - degrade carbohydrates into organic acids via the embden-meyerhof-parnas pathway and several of its branch pathways,resulting in dental caries,while alkalization and acid neutralization via the arginine deiminase system,urease,and so on,counteract acidification. proteolytic/amino acid-degrading bacteria,including prevotella and porphyromonas species,break down proteins and peptides into amino acids and degrade them further via specific pathways to produce short-chain fatty acids,ammonia,sulfur compounds,and indole/skatole,which act as virulent and modifying factors in periodontitis and oral malodor. furthermore,it is suggested that ethanol-derived acetaldehyde can cause oral cancer,while nitrate-derived nitrite can aid caries prevention and systemic health. microbial metabolic activity is influenced by the oral environment; however,it can also modify the oral environment,enhance the pathogenicity of bacteria,and induce microbial selection to create more pathogenic microbiome. taking a metabolomic approach to analyzing the oral microbiome is crucial to improving our understanding of the functions of the oral microbiome. © international & american associations for dental research 2015.