Desired Turbulence? Gut-Lung Axis, Immunity, and Lung Cancer

Table 1

Most frequently detected bacteria in GI tract and respiratory system of healthy volunteers or from healthy tissue samples. Results from different studies are presented by the taxa level in which they were originally detected, in order of decreasing abundance where possible. If the sampling, analysis method, or result was specific for a certain study, the reference was added adjacent to the corresponding information.

	Sample source; Analysis method	Phylum	Order or family	Genus or species	Reference
GI tract	Faeces; qPCR,; 16S sequencing	Firmicutes(79.4% of sequences), Bacteroidetes (16.9%), Actinobacteria (2.5%), Proteobacteria (1%), and Verrucomicrobia (0.1%)		Faecalibacterium, Ruminococcus, Eubacterium, Dorea, Bacteroides, Alistipes, and Bifidobacterium; Bacteroides (vulgatus), Roseburia (intestinalis), Ruminococcus (bromii), Eubacterium (rectale), Coprobacillus (sp.), Bifidobacterium (longum), and Clostridium (leptum, coccoides)	Tap et al. [11]
Oral cavity	Saliva; 16S sequencing	Firmicutes, Proteobacteria, Actinobacteria, Fusobacteria, TM7, and Spirochaetes	Pasteurellaceae (5.8%), Enterococcaceae (2.6%), Veillonellaceae (2.0%), Burkholderiales (1.2%), and Lactobacillales (1.1%)	Neisseria and Streptococcus (70% of sequences), Haemophilus (9.2%), Leptotrichia (2.1%), Actinomyces (1.9%), Abiotrophia (1.8%), Atopobium (1.6%), Gemella (1.6%), and Arthrobacter (1.0%)	Lazarevic et al. [12]
Nose	Swab; 16S sequencing	Actinobacteria, Firmicutes, Proteobacteria, Bacteroidetes, and Fusobacteria	Staphylococcaceae, Lachnospiraceae [13]; Propionibacteriaceae, Corynebacteriaceae [14]		Charlson et al. [14]; Lemon et al. [13]
Oropharynx	Swab; 16S sequencing	Dominated by Firmicutes, Proteobacteria, and Bacteroidetes, and Fusobacteria, Actinobacteria, TM7, and SR1 follow (oropharynx was richer and less variable than the nostril microbiota)	Streptococcaceae, Lachnospiraceae, unclassified group of Clostridia [13]; Streptococcaceae, Veillonellaceae, Fusobacteriaceae, and Neisseriaceae [14]		Charlson et al. [14]; Lemon et al. [13]
Esophagus	Biopsy; 16S sequencing	Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, Fusobacteria, and TM7		Streptococcus (mitis, thermophiles, parasanguis), Prevotella (pallens), Veillonella (atypica, dispar), Rothia (mucilaginosus), Megasphaera (micronuciformis), Granulicatella (adiacens), Gemella, TM7, Actinomyces (odontolyticus), Bacteroides, Clostridium, Haemophilus, and Bulleidia (moorei)	Pei et al. [15]
Lung	BAL, brushing; 16S sequencing	Actinobacteria, Firmicutes, and Proteobacteria [16]; Bacteroidetes, Firmicutes, Proteobacteria, Actinobacteria, andFusobacteria [7]	Streptococcaceae, Veillonellaceae, Prevotellaceae, Micrococcaceae, Neisseriaceae, Porphyromonadaceae, Lachnospiraceae, Actinomycetaceae, and Fusobacteriaceae [14]	Pseudomonas, Streptococcus, Prevotella, Fusobacterium, Haemophilus, Veillonella, and Porphyromonas [17]; Prevotella, Veillonella, other Firmicutes, other Bacteroidetes, Streptococcus, Haemophilus, Neisseria, Fusobacterium, other Actinobacteria, Staphylococcus, other Proteobacteria, and Corynebacterium [7]	Charlson et al. [14]; Erb-Downward et al. [17]; Hilty et al. [7]; Pragman et al. [16]

BAL: bronchoalveolar lavage.