Gut bacterial communities in sand fly vectors from Türkiye

Area of Science:

• Microbiology
• Entomology
• Vector Biology

Background:

• The gut microbiota of phlebotomine sand flies is crucial for their physiology and ability to transmit diseases like leishmaniasis.
• Factors influencing sand fly gut bacterial communities, particularly the role of host species, are not well understood.

Purpose of the Study:

• To investigate how different sand fly vector species influence their gut bacterial communities.
• To characterize the gut microbiota composition and functional potential in four sympatric sand fly species from Türkiye.
• To explore potential associations between gut microbiota and Leishmania parasite infection.

Main Methods:

• Gut bacterial communities of four sand fly species (Phlebotomus tobbi, P. sergenti s.l., P. papatasi, and P. major s.l.) were analyzed using 16S rRNA gene sequencing.
• Bioinformatic analyses (QIIME2, PICRUSt2) were used for taxonomic profiling and functional prediction.
• Leishmania spp. DNA was detected using internal transcribed spacer-1 (ITS-1) real-time PCR.

Main Results:

• Gut microbiota was dominated by Proteobacteria, with distinct species-specific profiles observed (e.g., Wolbachia in P. papatasi, Pseudomonas in P. major s.l.).
• Significant differences in alpha and beta diversity were found among the sand fly species, indicating host species specificity.
• Predicted functional analyses revealed largely conserved metabolic profiles across species.
• One Leishmania tropica-positive sample showed a distinct microbial composition dominated by Corynebacterium spp.

Conclusions:

• Sand fly species identity is a key determinant shaping the composition of their gut microbiota.
• Despite taxonomic variations, the overall metabolic potential of the gut microbiota appears conserved among sympatric sand fly species.
• Leishmania infection may be linked to alterations in the sand fly gut microbial community structure.