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3. Comparative analysis of the microbiota of sand fly vectors of Leishmania major and L. tropica in a mixed focus of cutaneous leishmaniasis in southeast Tunisia; ecotype shapes the bacterial community structure.

Author

Tabbabi, Ahmed, Mizushima, Daiki, Yamamoto, Daisuke S., Zhioua, Elyes, and Kato, Hirotomo

Subjects
*SAND flies, *CUTANEOUS leishmaniasis, *GUT microbiome, *LEISHMANIA major, *GENE amplification, *LEISHMANIA mexicana
Abstract

Phlebotomine sand flies are vectors of the protozoan parasite Leishmania spp. Although the intestinal microbiota is involved in a wide range of biological and physiological processes and has the potential to alter vector competence, little is known about the impact of host species and environment on the gut microbiome. To address this issue, a comparative analysis of the microbiota of sand fly vector populations of Leishmania major and L. tropica in a mixed focus of cutaneous leishmaniasis in Tunisia was performed. Bacterial 16S rRNA gene amplification and Illumina MiSeq sequencing were used to characterize and compare the overall bacterial and fungal composition of field-collected sand flies: Phlebotomus papatasi, Ph. perniciosus, Ph. riouxi, and Ph. sergenti. Thirty-eight bacterial genera belonging to five phyla were identified in 117 female specimens. The similarities and differences between the microbiome data from different samples collected from three collections were determined using principal coordinate analysis (PCoA). Substantial variations in the bacterial composition were found between geographically distinct populations of the same sand fly species, but not between different species at the same location, suggesting that the microbiota content was structured according to environmental factors rather than host species. These findings suggest that host phylogeny may play a minor role in determining the insect gut microbiota, and its potential to affect the transmission of the Leishmania parasite appear to be very low. These results highlight the need for further studies to decode sand fly Leishmania-microbiota interactions, as even the same bacterial species, such as Enterococcus faecalis, can exert completely opposite effects when confronted with different pathogens within various host insects and vice versa. Author summary: Leishmania major and L. tropica are the causative agents of cutaneous leishmaniasis in the Tataouine governorate of southeast Tunisia. In this study, the microbiota of Phlebotomus papatasi, Ph. perniciosus, Ph. riouxi, and Ph. sergenti, which were caught from three diverse ecotypes, were analyzed using 16S rRNA gene amplification and Illumina MiSeq sequencing. In total, 117 Leishmania-free and blood-non-fed female specimens were used individually in this study to avoid any bias caused by pooling samples. We found that the gut microbiota was mainly controlled by environmental habitats and other factors, as remarkable differences in microbiota composition within the same species collected from the same location was revealed. Moreover, the results suggested that host phylogeny may play a minor role in determining the insect gut microbiota, and the potential of the host factor to affect the transmission of the Leishmania parasite appeared to be very low. A better understanding of microorganism-insect-gut bacterial interactions is critical, as the interactions between pathogens and gut microbiota do not adhere to a consistent pattern of synergy or antagonism. Even the same bacterial species, such as Enterococcus faecalis, can exert opposing effects when confronted with different pathogens in various host insects [ABSTRACT FROM AUTHOR]

Published
2024
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14. A rare sugar, allose, inhibits the development of Plasmodium parasites in the Anopheles mosquito independently of midgut microbiota.

Author

Daiki Mizushima, Yamamoto, Daisuke S., Tabbabi, Ahmed, Meiji Arai, and Hirotomo Kato

Subjects
PLASMODIUM, ANOPHELES, ANOPHELES stephensi, MOSQUITOES, PLASMODIUM berghei, POLYOLS, PARASITES
Abstract

A rare sugar, allose, was reported to inhibit the development of Plasmodium parasites in Anopheles mosquitoes; however, the mechanism remains unknown. The present study addressed the inhibitory mechanism of allose on the development of the Plasmodium parasite by connecting it with bacteria involvement in the midgut. In addition, further inhibitory sugars against Plasmodium infection in mosquitoes were explored. Antibiotic-treated and antibiotic-untreated Anopheles stephensi were fed fructose with or without allose. The mosquitoes were infected with luciferase-expressing Plasmodium berghei, and parasite development was evaluated by luciferase activity. Bacterial composition analysis in gut of their mosquitoes was performed with comprehensive 16S ribosomal RNA sequencing. As the result, allose inhibited the development of oocysts in mosquitoes regardless of prior antibiotic treatment. Microbiome analysis showed that the midgut bacterial composition in mosquitoes before and after blood feeding was not affected by allose. Although allose inhibited transient growth of the midgut microbiota of mosquitoes after blood feeding, neither toxic nor inhibitory effects of allose on the dominant midgut bacteria were observed. Ookinete development in the mosquito midgut was also not affected by allose feeding. Additional 15 sugars including six monosaccharides, four polyols, and five polysaccharides were tested; however, no inhibitory effect against Plasmodium development in mosquitoes was observed. These results indicated that allose inhibits parasite development in midgut stage of the mosquito independently of midgut microbiota. Although further studies are needed, our results suggest that allose may be a useful material for the vector control of malaria as a “transmissionblocking sugar.” [ABSTRACT FROM AUTHOR]

Published
2023
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24. Further insight into the geographic distribution of Leishmania species in Peru by cytochrome b and mannose phosphate isomerase gene analyses

Author

Kato, Hirotomo, primary, Cáceres, Abraham G., additional, Seki, Chisato, additional, Silupu García, Carmen Rosa, additional, Holguín Mauricci, Carlos, additional, Castro Martínez, Salvadora Concepción, additional, Moreno Paico, Dafne, additional, Castro Muniz, Josefa Leila, additional, Troyes Rivera, Lucinda Doriz, additional, Villegas Briones, Zoila Isabel, additional, Guerrero Quincho, Silvia, additional, Sulca Jayo, Guísela Lucy, additional, Tineo Villafuerte, Edwin, additional, Manrique de Lara Estrada, Carlos, additional, Arias, Fernando Rafael, additional, Passara, Fredy Santiago, additional, Ruelas Llerena, Nancy, additional, Kubo, Makoto, additional, Tabbabi, Ahmed, additional, Yamamoto, Daisuke S., additional, and Hashiguchi, Yoshihisa, additional

Published
2019
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26. PCR-RFLP analyses of Leishmania species causing cutaneous and mucocutaneous leishmaniasis revealed distribution of genetically complex strains with hybrid and mito-nuclear discordance in Ecuador

Author

Kato, Hirotomo, primary, Gomez, Eduardo A., additional, Seki, Chisato, additional, Furumoto, Hayato, additional, Martini-Robles, Luiggi, additional, Muzzio, Jenny, additional, Calvopiña, Manuel, additional, Velez, Lenin, additional, Kubo, Makoto, additional, Tabbabi, Ahmed, additional, Yamamoto, Daisuke S., additional, and Hashiguchi, Yoshihisa, additional

Published
2019
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41. Pirimiphos-methyl Resistance in Culex pipiens (Diptera: Culicidae) in Southern Tunisia

Author

Ben Cheikh Raja, Ben Cheikh Hassen, Daaboub Jaber, Tabbabi Ahmed, and Laamari Ali

Subjects
education.field_of_study, Veterinary medicine, Resistance (ecology), biology, fungi, Population, Pirimiphos-methyl, Propoxur, biology.organism_classification, Esterase, chemistry.chemical_compound, Geography, chemistry, Organophosphorus insecticide, Culex pipiens, South east, education, Demography
Abstract

Pirimiphos-methyl is an organophosphorus insecticide having a fast action with less toxicity for humans and environment. The aim of this study was to investigate the pirimiphos-methyl resistance of three populations of Culex pipiens in southern Tunisia. Three Culex pipiens samples were collected in 3 localities (South east, south west, and extreme south) of southern Tunisia between March 2002 and October 2005. The susceptibility of the third population (extreme south) of Culex pipiens to pirimiphos-methyl was not considered due to control-level mortality. Both other studied samples were resistant to pirimiphos methyl and to propoxur. A significantly correlation was observed between the mortality due to propoxur and the LC50 of pirimiphos methyl (P

Published
2017
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