Project description:Folic acid deficiency is common worldwide and is linked to intestinal flora imbalance. The intestinal microbial utilization of folic acid based on model animals faces the challenges of repeatability and individual variability. In this study, we built an in vitro fecal slurry culture model deficient in folic acid. We examined the effects of supplementation with different forms of folic acid (5-methyltetrahydrofolate and non-reduced folic acid) on the modulation of intestinal flora. 16S rDNA gene sequencing showed alpha diversity increased after folic acid supplementation compared to fermentation samples with folic acid deficiency. In the non-reduced folic acid (FA) group, the relative abundance of the Firmicutes phylum dropped to 56.7%, whereas in the 5-methyltetrahydrofolate (MTHF) supplementation group, it grew to 64.9%. Lactobacillus genera became more prevalent, reaching 22.8% and 30.8%, respectively. Additionally, Bifidobacterium and Pedioccus, two common probiotic bacteria, were in higher abundance. Short-chain fatty acids (SCFAs) analysis showed that supplementation with folic acid (non-reduced folic acid, 5-methyltetrahydrofolate) decreased acetic acid and increased the fermentation yield of isobutyric acid. The in vitro fecal slurry culture model developed in this study can be utilized as a human folic acid deficiency model for studying intestinal microbiota and demonstrated that both 5-methyltetrahydrofolate and non-reduced folic acid have effects on the regulation of intestinal microecology.
Project description:Mitochondrial rRNAs play important roles in regulating mtDNA-encoded gene expression and energy metabolism subsequently. However, the proteins that regulate mitochondrial 16S rRNA processing remain poorly understood. Herein, we generated adipose-specific Wbscr16-/- mice and cells, both of which exhibited dramatic mitochondrial changes. Subsequently, WBSCR16 was identified as a 16S rRNA-binding protein essential for the cleavage of 16S rRNA-mt-tRNALeu, facilitating 16S rRNA processing and mitochondrial ribosome assembly. Additionally, WBSCR16 recruited RNase P subunit MRPP3 to nascent 16S rRNA and assisted in this specific cleavage. Furthermore, evidence showed that adipose-specific Wbscr16 ablation promotes energy wasting via lipid preference in brown adipose tissue, leading to excess energy expenditure and resistance to obesity. In contrast, overexpression of WBSCR16 upregulated 16S rRNA processing and induced a preference for glucose utilization in both transgenic mouse models and cultured cells. These findings suggest that WBSCR16 plays essential roles in mitochondrial 16S rRNA processing in mammals, and is the key mitochondrial protein to balance glucose and lipid metabolism.
Project description:Anaerobic bacteria in the oral cavity can cause respiratory infections. However, their precise mechanisms of action remain elusive. Unexpectedly, bacterial flora analysis using 16s rRNA revealed ‘hidden’ mixed infections of anaerobic bacteria and commensal oral Streptococcus species in community-acquired pneumonia. The purpose of this study is to elucidate the mechanisms by which Prevotella intermedia exacerbates oral streptococcal pneumonia.
