Table 1.

Predominat bacteria in specific body site

	Predominant phyla	Reference
Body site
Mouth	Firmicutes (e.g., Streptococcus); Bacteroidetes (e.g., Prevotella); Proteobacteria (e.g., Haemophilus); Actinobacteria (e.g., Actinomyces); Spirochaetes (e.g., Treponema); Fusobacteria (e.g., Fusobacterium)	[154–156]
Nose	Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria	[157]
Lung	Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria	[80]
Skin	Actinobacteria (Propionibacterium, Corynebacterium) and Firmicutes (Staphylococcus)	[89, 90]
Gut	Firmicutes (e.g., Lachnospiraceae, Ruminococcaceae), Bacteroidetes (e.g., Bacteroides and/or Prevotella, depending on ethnicity), Actinobacteria (Bifidobacterium, in different abundance according to the host’s age)	[37, 41, 42]
Vagina	Firmicutes (Lactobacillus)	[104, 107, 110]
Genito-urinary tract	Actinobacteria (Gardnerella, Corynebacterium) and Firmicutes (Lactobacillus, Streptococcus)	[128–131, 141]