Unraveling the impact of primary immunodeficiency disorders on the microbiota of dental caries in children through 16S rRNA gene-based metagenomic analysis.

Background/aim: Dental caries is a frequently occurring and multifactorial chronic disease in children resulting from the interaction of cariogenic bacteria and host susceptibility. The aim of this study was to elucidate the impacts of primary immunodeficiency disorders (PIDs) on microbiota of dental caries in children by 16S rRNA gene-based metagenomic analysis. Materials and methods: Enrolled in this study were 15 children with primary PID with caries (PID group) and 15 healthy children with caries as a control (CG). The DMFT index, saliva flow rate, and buffering capacity of each participant were assessed before the metagenomic analyses were conducted. For taxonomic profiling, the reads were obtained by high-throughput sequencing of the V3-V4 hypervariable region of 16S rRNA. Results: The DMFT score, saliva flow rate, and buffering capacity of the groups were similar. The flow rate and buffering capacity had no correlation with the number of species with 95% confidence. The metagenomic analysis resulted in the identification of 2440 bacterial species in all of the samples. Among the 50 most prevalent species present at ≥1% relative abundance, Prevotella melaninogenica and Prevotella salivae were differentially more abundant in the PID group. The PID group and CG showed similar species richness and evenness, but 4 of the 5 samples with the highest Shannon-Weiner and Inverse Simpson indices belonged to the PID group. The Spearman test results for correlation of the species in the PID subgroups showed that Prevotella oris had a positively correlated relationship with both Scardovia wiggsiae and Saccharibacteria genera incertae sedis. Conclusion: This study provided insight into the caries microbiota of children with immunodeficiency diseases. Differentially abundant species, novel bacterial associations, and unique bacterial species were disclosed in the PID samples, indicating the role of the immune system in altering the caries microbiota. The prominent bacterial species and associations in the PID group should be suspected in regard to their link with present or future diseases.

Implications from a pharmacogenomic analysis: Nerium oleander leaf distillate supplemented diet regulates cholesterol metabolism in rats.

CONTEXT: Despite the usage of Nerium oleander L. (Apocynaceae) for anticancer studies and traditional remediation, the regulatory effect of N. oleander leaf distillate on cholesterol metabolism is not disclosed sufficiently. OBJECTIVE: Cholesterol is an important biological molecule and the synthesis rate is regulated by the amount of cholesterol uptake from the diet. The aim of this study was to investigate the regulation of cholesterol metabolism in response to a high-fat diet (HFD) and the effects of N. oleander leaf distillate-supplemented diet (NOHFD) in rats. MATERIALS AND METHODS: Microarray technology was used to clarify the regulation of cholesterol mechanism in HFD and NOHFD-fed rats (375 µg/0.5 mL distilled water applied by gavage). The treatment period was 90 days. Rat liver tissues were used for microarray analysis using the Affymetrix GeneChip Rat Genome platform. RESULTS of groups were statistically analyzed with the Partek 6.6 bioinformatic program. RESULTS: The HFD group exhibited alterations in the expression levels of about 1945 genes with respect to the normal diet (ND) group. The results showed that expression levels of 47 genes were altered related to cholesterol metabolism in HFD and NOHFD groups. The expression levels of seven genes in the NOHFD group were significantly closer to those in the ND group than those of the HFD group. DISCUSSION AND CONCLUSION: To conclude, findings suggest that N. oleander leaf distillate-supplemented food has considerable beneficial effects on cholesterol metabolism-related gene expression levels.

Heterologous expression of glutamyl-tRNA reductase gene in Rhodobacter sphaeroides O.U.001 to enhance 5-aminolevulinic acid production.

The pathways for synthesis of 5-aminolevulinic acid (5-ALA) use either succinyl-CoA and glycine (C-4 pathway), or glutamate (C-5 pathway). Although Rhodobacter sphaeroides synthesizes 5-ALA through the C-4 pathway, it also has the genes coding for the enzymes of the C-5 pathway, except for glutamyl-tRNA reductase. The glutamyl-tRNA reductase gene was cloned from Rhodospirillum rubrum and expressed in R. sphaeroides; thus, the C-5 pathway was enabled to function upon assembling all the required genes. Consequently, a new and unique bacterial strain producing more 5-ALA was developed. Biohydrogen was also produced in the same bioprocess within a biorefinery approach using sugar beet molasses as substrate. The amount of 5-ALA produced by the modified strain was 25.9 mg/g dry cell weight (DCW), whereas the wild-type strain produced 12.4 mg/g DCW. In addition, the amount of H2 generated by the modified and wild-type cells, respectively, was 0.92 L/L culture and 1.05 L/L culture.