A comparative study of the oral microbiome compositions of healthy postmenopausal, premenopausal, and prepubertal Nigerian females, using 16S rRNA metagenomics methods

Abstract

Introduction: There is a paucity of information on the oral microbiome compositions of Nigerians, mostly due to lack of appropriate molecular techniques. In this pilot study, we sought to determine and characterize the oral bacterial compositions of “healthy” females.

Materials and Methods: Oral samples were collected from three randomly selected females aged 56, 28, and 8 years. DNA was extracted and 16S rRNA V4 region was amplified using custom‑barcoded primers before sequencing with Illumina MiSeq platform. Quantitative Insights into Microbial Ecology pipeline was used for 16S rRNA recognition. Distribution of taxonomic categories at different levels of resolution was done using the ribosomal RNA similarities to entries in the REFseq protein database. Diversity score was calculated based on the inverse Simpson’s index.

Results: The inverse Simpson’s diversity index for the postmenopausal, premenopausal, and prepubertal was 7.74, 6.95, and 7.42 respectively. A total of 12 phyla, 70 genera, and 85 species were detected. Firmicutes followed by Proteobacteria, Actinobacteria, Bacteroidetes, and Fusobacteria dominated the oral microbiome of the subjects. Streptococcus thermophilus (33.19%) was the most abundance species in subject 1, while subject 2 was highly predominated by Haemophilus parainfluenzae (80.65%), and subject 3 was predominated by Haemophilus influenzae (23.05%).

Conclusion: The study has revealed that bacteria with varying diversities colonized the subjects and it highlighted the importance of metagenomics in deciphering the oral bacterial compositions from females of different age groups. More studies are needed using metagenomics approach, to appreciate these bacterial organisms that are associated with health and disease in our environment.

Keywords: Metagenomics, Nigerian females, oral microbiome