Fig. 1

Functional, ecological and epidemiological features of saliva microbiota. a The conservation and divergence of gene sequences and encoded functions among the four sequenced human saliva microbiota. b Functional signatures of human saliva microbiota. Blocks of gene categories relatively enriched (in red) or depleted (in green) in each microbiota were highlighted. Comparison of the microbiota was based on functional annotations on MG-RAST Subsystem Level 2. c Functional clustering of microbiota from different mammals or body sites. They include human mouth [including saliva, supragingival dental plaques (Belda-Ferre et al. 2012) and cavities plaques (Belda-Ferre et al. 2012)], human gut (Turnbaugh et al. 2009a, b) and cow rumen (originated from MG-RAST server). Results were generated by Principal Component Analysis (PCA). d Functional clustering of oral microbiota from different oral sites or host states. Those from saliva [both healthy and caries-active (DMFT ≧ 6)], supragingival dental plaques [both healthy and caries-active (DMFT ≧ 6)] and cavities plaques were shown