title: An integrated overview of the midgut bacterial flora composition of Phlebotomus perniciosus, a vector of zoonotic visceral leishmaniasis in the Western Mediterranean Basin.
abstract: The Leishmania developmental life cycle within its sand fly vector occurs exclusively in the lumen of the insect's digestive tract in the presence of symbiotic bacteria. The composition of the gut microbiota and the factors that influence its composition are currently poorly understood. A set of factors, including the host and its environment, may influence this composition. It has been demonstrated that the insect gut microbiota influences the development of several human pathogens, such as Plasmodium falciparum. For sand flies and Leishmania, understanding the interactions between the parasite and the microbial environment of the vector midgut can provide new tools to control Leishmania transmission.
  
  
  
  The midguts of female Phlebotomus perniciosus from laboratory colonies or from the field were collected during the months of July, September and October 2011 and dissected. The midguts were analyzed by culture-dependent and culture-independent methods. A total of 441 and 115 cultivable isolates were assigned to 30 and 11 phylotypes from field-collected and colonized P. perniciosus, respectively. Analysis of monthly variations in microbiota composition shows a species diversity decline in October, which is to the end of the Leishmania infantum transmission period. In parallel, a compilation and a meta-analysis of all available data concerning the microbiota of two Psychodidae genera, namely Phlebotomus and Lutzomyia, was performed and compared to P. perniciosus, data obtained herein. This integrated analysis did not reveal any substantial divergences between Old and New world sand flies with regards to the midgut bacterial phyla and genera diversity. But clearly, most bacterial species (>76%) are sparsely distributed between Phlebotominae species.
  
  
  
  Our results pinpoint the need for a more exhaustive understanding of the bacterial richness and abundance at the species level in Phlebotominae sand flies in order to capture the role of midgut bacteria during Leishmania development and transmission. The occurrence of Bacillus subtilis in P. perniciosus and at least two other sand fly species studied so far suggests that this bacterial species is a potential candidate for paratransgenic or biolological approaches for the control of sand fly populations in order to prevent Leishmania transmission.
authors.affiliation: Laboratory of Vector Ecology, Pasteur Institute of Tunis, Tunis, Tunisia.|Laboratory of Microorganisms and Active Biomolecules, University of Tunis-El Manar, Faculty of Sciences, Tunis, Tunisia.
authors.forename: Wael
authors.initials: W
authors.lastname: Fraihi
authors.affiliation: Laboratory of Vector Ecology, Pasteur Institute of Tunis, Tunis, Tunisia.
authors.forename: Wasfi
authors.initials: W
authors.lastname: Fares
authors.affiliation: MIVEGEC/Université de Montpellier CNRS/UMR 5244/IRD 224 - Centre IRD, Montpellier, France.
authors.forename: Pascale
authors.initials: P
authors.lastname: Perrin
authors.affiliation: INRA - UMR 1062 CBGP (INRA, IRD, CIRAD), Montpellier SupAgro, Montferrier-Sur-Lez, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Dorkeld
authors.affiliation: MIVEGEC/Université de Montpellier CNRS/UMR 5244/IRD 224 - Centre IRD, Montpellier, France.|UMR177, Centre IRD de Montpellier, Montpellier, France.
authors.forename: Denis
authors.identifier: 0000-0002-0034-9291
authors.initials: D
authors.lastname: Sereno
authors.affiliation: Laboratory of Vector Ecology, Pasteur Institute of Tunis, Tunis, Tunisia.
authors.forename: Walid
authors.initials: W
authors.lastname: Barhoumi
authors.affiliation: Laboratory of Microorganisms and Active Biomolecules, University of Tunis-El Manar, Faculty of Sciences, Tunis, Tunisia.
authors.forename: Imed
authors.initials: I
authors.lastname: Sbissi
authors.affiliation: Laboratory of Vector Ecology, Pasteur Institute of Tunis, Tunis, Tunisia.
authors.forename: Saifedine
authors.initials: S
authors.lastname: Cherni
authors.affiliation: Laboratory of Vector Ecology, Pasteur Institute of Tunis, Tunis, Tunisia.
authors.forename: Ifhem
authors.initials: I
authors.lastname: Chelbi
authors.affiliation: Division of Infectious Diseases, Center for Global Health, Department of Internal Medicine, UNM School of Medicine Albuquerque, New Mexico, United States of America.
authors.forename: Ravi
authors.initials: R
authors.lastname: Durvasula
authors.affiliation: Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Maryland, United States of America.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Ramalho-Ortigao
authors.affiliation: Laboratory of Microorganisms and Active Biomolecules, University of Tunis-El Manar, Faculty of Sciences, Tunis, Tunisia.
authors.forename: Maher
authors.initials: M
authors.lastname: Gtari
authors.affiliation: Laboratory of Vector Ecology, Pasteur Institute of Tunis, Tunis, Tunisia.
authors.forename: Elyes
authors.initials: E
authors.lastname: Zhioua
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D001431:Bacteriological Techniques; D000069196:Gastrointestinal Microbiome; D007303:Insect Vectors; D019083:Mediterranean Region; D056186:Metagenomics; D010691:Phlebotomus / Q000382:microbiology*; D012621:Seasons; D017422:Sequence Analysis, DNA