Investigation of gut microbiota composition in humans carrying blastocystis subtypes 1 and 2 and Entamoeba hartmanni

The composition of human gut microbiota is dominated by bacteria which have been extensively studied. The role of intestinal eukaryote microorganisms like Blastocystis, however, remains under investigation. Moreover, the potential impact on gut health related to Blastocystis presence was primarily investigated in symptomatic individuals mainly from industrialized countries, and appears to be mostly beneficial to the host microbiota. Data from surveys conducted in underdeveloped countries with higher prevalence and from asymptomatic individuals could therefore be valuable. The aim of this preliminary study was to analyze the composition of the gut microbiota in relation to the protozoa Blastocystis ST1 and ST2 and Entamoeba hartmanni carriage in asymptomatic subjects living in a semi-urban area of Côte d'Ivoire to add data into the ongoing debate on the role of Blastocystis in host health. The amplification of the V3 and V4 regions of bacterial 16S rDNA genes was performed to obtain the gut microbiota composition, and differential analyses on alpha and beta diversity were performed from the phylum to genus taxonomic level. The analysis revealed that individuals positive for both protozoa exhibited higher alpha and beta diversity compared to those who tested negative. Additionally, their bacterial composition showed a reduction in Bacteroides and an increase in Prevotella 9. Relative abundances of some OTUs, particularly Faecalibacterium, observed in individuals who tested positive for protozoa, were correlated with a good state of health of the gut microbiota. Blastocystis ST1 and ST2 associated with E. hartmanni thus appeared to be related to a state of intestinal eubiosis.