Thus, even though much of the actual food sources overlap between the human workers and the apes at each sanctuary, this seems to have at best a minor effect on their saliva microbiomes. However, other potential influences on the saliva microbiome (disease status, actual individual nutrition, etc.) were not available and hence remain to be investigated. Both the human and ape salivary microbiome Milciclib nmr was dominated by Proteobacteria, followed by Firmicutes in Pifithrin�� humans and Bacteroidetes in apes. Actinobacteria were much more dominant in
apes than in humans. Those differences in phyla distribution between humans and apes are within the range that has previously been reported among humans . Hence, at the phylum level the saliva microbiome of humans and apes does not differ dramatically. Within Proteobacteria, both humans and apes are characterized by high proportions of Enterobacteriaceae, which is in agreement with our previous analysis of African populations [14, 15] but which stands in stark contrast to other recent oral microbiome studies that focused mainly on individuals of European ancestry [26–28]. Enterobacteriaceae are known to emerge in the oral cavity with increasing age and they selleck screening library can act as opportunist pathogens, especially in patients with debilitating diseases who are submitted to prolonged treatments with antibiotics or
cytotoxic medications . Although few studies have explicitly analyzed the occurrence of Enterobacteriaceae in the oral cavity of healthy individuals, they have been reported in nasopharyngeal swabs from northern Africans  and in the anterior nares of African-Americans . We conclude that Enterobactericeae may be a consistent marker bacterial family that distinguishes African populations from other world-wide geographical regions. The reason for the higher abundance of Enterobacteriaceae in African populations remains unknown; knowledge of precise species would help elucidate the source of enterobacterial
for colonization (uptake of free-living species from plants, or introduction through consumption of fecal-contaminated food or water). In addition to the Proteobacteria, most genera within the Firmicutes, Actinobacteria, Fusobacteria and Bacteroidetes were either consistently higher or lower in one group compared to the other. Such consistencies may support the concept of an ecological coherence of high bacterial taxonomic ranks, as discussed previously . This means that bacterial taxa in a given phylum or family exhibit similar ecological traits, allowing the occupation of similar niches in a given host. Since obligate anaerobic bacteria (e.g., Fusobacteria and Bacteroidetes) occurred at much higher levels in sanctuary apes than in humans, differential oxygen levels might be one driving physical factor shaping the oral habitats represented by the salivary microbiome in humans and apes.