High-throughput Sequencing Analysis and Function Prediction of Lung Microbiota in Healthy Rats

To form the basis of a respiratory disease model in rats by investigating the microbial distribution and composition in the lower respiratory tracts of normal rats. Methods: DNA was extracted from the intestine, trachea, bronchus and lung samples collected from healthy rats under sterile conditions. The 16S rDNA V4-V5 region was sequenced using Illumina high-throughput technology. Results: The sequencing results showed that there was no significant difference in abundance and species diversity of microbiota between the lower respiratory and the intestine. The microbiota structure analysis showed samples from lungs and intestinal shared similarity. However, the dominant species at the levels of phylum, family, and genus diverged. The similarity analysis showed that the lung microbiota were different from the intestines. The linear discriminant analysis showed significantly different species in different tissues; function prediction also showed different microbiota function in different tissues. Conclusions: These results suggest that bacterial colonization depends on the sample's anatomical location. The human pathogen Acinetobacter lwoffii was also detected in the rat lower respiratory tract samples.