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Bandibabone, J.

Publications and source records attributed to Bandibabone, J..

3 recordsLinked to original sources

Optimising the use of Oxford Nanopore Sequencing technology for detection of Wolbachia bacterial endosymbionts in Anopheles mosquitoes.

Malaria, a mosquito-borne disease predominantly affecting sub-Saharan Africa, remains a significant global health challenge with 263 million cases in 2023. Although progress in vaccine development has recently occurred, insecticide resistance has reduced the effectiveness of the main stay method of traditional vector control and novel innovative vector control strategies against Anopheles mosquitoes is crucial to combat the spread of malaria. Wolbachia is an endosymbiotic bacterium that can invade mosquito populations and inhibit human pathogens. Historically Wolbachia was thought to not occur naturally within wild Anopheles An.) populations, but recent evidence has confirmed the presence of at least two strains in genuine symbiosis. Detection of Wolbachia strains has pre-dominantly relied on PCR amplification of Wolbachia genes and/or sanger and illumina sequencing. In this study, we assess the use of Oxford Nanopore Technology (ONT) for detecting bacteria within wild Anopheles mosquitoes and determine the ability to detect the endosymbiotc bacterium Wolbachia. We assessed Wolbachia detection from library preparations using the ONT Field sequencing kit for MinION sequencing on the Mk1C and found a pool size of 10 mosquitoes is required preventing individual mosquito analysis. There were roughly 13 times more Wolbachia reads in pooled Anopheles demeilloni compared to An. gambiae. Utilizing the more economical Flongle flow cells and Mk1B device, we further evaluated the effectiveness of two library preparation methods that are compatible: Rapid PCR Barcoding and 16S Barcoding kits. Our findings indicate that the 16S Barcoding Kit in conjunction with the Flongle flowcell effectively identified Wolbachia in both Anopheles demeilloni and Anopheles moucheti but we found no evidence of Wolbachia in Anopheles gambiae. Our study demonstrates the feasibility of developing ONT for field-based sequencing in malaria-endemic regions, providing a potentially lower cost and field friendly method for monitoring mosquito populations and associated endosymbionts. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=196 SRC="FIGDIR/small/659891v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@18ee91dorg.highwire.dtl.DTLVardef@16a71c4org.highwire.dtl.DTLVardef@15330edorg.highwire.dtl.DTLVardef@b13e3d_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Genomic and microscopic evidence of stable high density and maternally inherited Wolbachia infections in Anopheles mosquitoes

Wolbachia, a widespread bacterium that can reduce pathogen transmission in mosquitoes, has been detected within populations of Anopheles (An.) malaria vectors. In the An. gambiae complex, the primary vectors in Sub-Saharan Africa, Wolbachia strains are at low density and infection frequencies in wild populations. PCR-independent evidence is required to determine whether Wolbachia strains are true endosymbionts in Anopheles given most studies to date have used nested-PCR to identify strains. Here we report high-density strains found in geographically diverse populations of An. moucheti and An. demeilloni. Fluorescent in situ hybridization localized a heavy infection in the ovaries of An. moucheti and maternal transmission was observed. Genome sequencing of both strains obtained genome depths and coverages comparable to other known infections. Notably, homologs of cytoplasmic incompatibility factor (cif) genes were present indicating these strains possess the capacity to induce the phenotype cytoplasmic incompatibility which allows Wolbachia to spread through populations. The characteristics of these two strains suggest they are ideal candidates for Wolbachia biocontrol strategies in Anopheles.

microbiology↗

Novel Wolbachia strains in Anopheles malaria vectors from Sub-Saharan Africa

Anopheles (An.) mosquitoes contain bacteria that can influence Plasmodium parasites. Wolbachia, a common insect endosymbiont, has historically been considered absent from Anopheles but has recently been found in An. gambiae populations. Here, we assessed a range of Anopheles species from five malaria-endemic countries for Wolbachia and Plasmodium infection. Strikingly, we found Wolbachia infections in An. coluzzii, An. gambiae s.s, An. arabiensis, An. moucheti and An. species A increasing the number of Anopheles species known to be naturally infected by this endosymbiont. Molecular analysis suggests the presence of phylogenetically diverse novel strains, while qPCR and 16S rRNA sequencing indicates that Wolbachia is the dominant member of the microbiota in An. moucheti and An. species A. We found no evidence of Wolbachia/Asaia co-infections, and presence of these endosymbionts did not have significant effects on malaria prevalence. We discuss the importance of novel Wolbachia strains in Anopheles and potential implications for disease control.

microbiology↗