Abstract: Objective: To investigate the effects of pyrazinamide on intestinal flora in mice. Methods: A solvent control group, a lowdose
pyrazinamide group and a high-dose pyrazinamide group were set up with 10 mice in each group. Three groups of fresh feces were
collected for 16S rRNA sequencing and analyzed by bioinformatics methods to determine the diversity of mouse intestinal flora.
Results: At the phylum level, the low-dose group, the high-dose group, and the solvent control group are dominated by Bacteroidetes
and Firmicutes, and their dominant flora accounted for 47.02%, 51.46%, 56.24%, 41.65%, 76.14% and 20.83%, respectively. At the
genus level, the low-dose group is dominated by Bacteroides（8.42%）and Oscillospira（1.41%）; the high-dose group is dominated by
Lactobacillus（2.74%）, Odoribacter（1.20%）and Bacteroides（1.14%）; the solvent control group is mainly Prevotella（3.54%）and
Bifidobacterium（1.81%）. Compared with the solvent control group, the amino acid, energy and polysaccharide metabolism of the
pyrazinamide group were significantly reduced（P < 0.05）. Conclusion: Pyrazinamide can change the composition and metabolic
function of intestinal flora.

Key words: pyrazinamide, intestinal flora, 16S rRNA