Microbiota identified from preserved Anopheles

• Published in: Malaria journal Vol. 20; no. 1; pp. 1 - 230
• Main Authors: E Silva, Bianca, Matsena Zingoni, Zvifadzo, Koekemoer, Lizette L, Dahan-Moss, Yael L
• Format: Journal Article Web Resource
• Language: English
• Published: London BioMed Central Ltd 22.05.2021; BioMed Central; BMC
• Subjects: Abdomen; Animals; Anopheles; Anopheles arabiensis; Anopheles funestus; Aquatic insects; Bacteria; Culicidae; Culturomics; Dissection; Diversity indices; DNA; DNA sequencing; Ethanol; Females; Human diseases; Infectious Diseases; Insects as carriers of disease; Laboratories; Life sciences; Malaria; Methods; Microbiota; Microbiota (Symbiotic organisms); Midgut; Mosquito Vectors; Mosquitoes; Next-generation sequencing; Nucleic acids; Parasitology; Physiological aspects; Preservation; Preservation, Biological; Preservatives; RNAlater; Sciences du vivant; Silica; South Africa; Specimen Handling; Vector-borne diseases; Vectors; South Africa
• ISSN: 1475-2875; 1475-2875
• DOI: 10.1186/s12936-021-03754-7

Abstract Background Mosquito species from the Anopheles gambiae complex and the Anopheles funestus group are dominant African malaria vectors. Mosquito microbiota play vital roles in physiology and vector competence. Recent research has focused on investigating the mosquito microbiota, especially in wild populations. Wild mosquitoes are preserved and transported to a laboratory for analyses. Thus far, microbial characterization post-preservation has been investigated in only Aedes vexans and Culex pipiens . Investigating the efficacy of cost-effective preservatives has also been limited to AllProtect reagent, ethanol and nucleic acid preservation buffer. This study characterized the microbiota of African Anopheles vectors: Anopheles arabiensis (member of the An. gambiae complex) and An. funestus (member of the An. funestus group), preserved on silica desiccant and RNA later ® solution. Methods Microbial composition and diversity were characterized using culture-dependent (midgut dissections, culturomics, MALDI-TOF MS) and culture-independent techniques (abdominal dissections, DNA extraction, next-generation sequencing) from laboratory (colonized) and field-collected mosquitoes. Colonized mosquitoes were either fresh (non-preserved) or preserved for 4 and 12 weeks on silica or in RNA later ® . Microbiota were also characterized from field-collected An. arabiensis preserved on silica for 8, 12 and 16 weeks. Results Elizabethkingia anophelis and Serratia oryzae were common between both vector species, while Enterobacter cloacae and Staphylococcus epidermidis were specific to females and males, respectively. Microbial diversity was not influenced by sex, condition (fresh or preserved), preservative, or preservation time-period; however, the type of bacterial identification technique affected all microbial diversity indices. Conclusions This study broadly characterized the microbiota of An. arabiensis and An. funestus . Silica- and RNA later ® -preservation were appropriate when paired with culture-dependent and culture-independent techniques, respectively. These results broaden the selection of cost-effective methods available for handling vector samples for downstream microbial analyses.