Wickerhamomyces anomalus in Mosquitoes: A Promising Yeast-Based Tool for the “Symbiotic Control” of Mosquito-Borne Diseases

The ascomycete yeast Wickerhamomyces anomalus is a mutualistic symbiont of different insects, including diptera vectors of diseases. Although fungal symbioses have been so far poorly characterized, the topic is gaining attention as yeast-insect interactions can provide pivotal information on insect biology, such as their environmental adaptation or vectorial capability. We review the symbiosis between W. anomalus and mosquitoes, which implies nutritional and protective functions. Furthermore, we focus on antiplasmodial effects of W. anomalus in malaria vectors and discuss the yeast potential for the “symbiotic control” (SC) of mosquito-borne diseases (MBDs).

Candidates for Symbiotic Control of Sugarcane White Leaf Disease

ABSTRACTThe leafhopperMatsumuratettix hiroglyphicus(Matsumura) is the most important vector of a phytoplasma pathogen causing sugarcane white leaf (SCWL) disease. The purpose of this study was to evaluate candidate bacterial symbionts for possible use as vehicles in the control of the disease. 16S rRNA bacterial genes were amplified from whole bodies ofM. hiroglyphicusleafhoppers and analyzed by cloning and sequencing. Two dominant groups were found: one belonged to theBetaproteobacteriathat did not closely match any sequences in the database and was named bacterium associated withM. hiroglyphicus(BAMH). Another one found to be abundant in this leafhopper is “CandidatusSulcia muelleri” in the orderBacteroidetes, which was previously reported in the insect members of the Auchenorrhyncha. MostM. hiroglyphicusleafhoppers carry both BAMH and “Ca. Sulcia muelleri.” Fluorescentin situhybridization showed that BAMH and “Ca. Sulcia muelleri” colocalized in the same bacteriomes. BAMH was present in the midgut and ovaries of the leafhopper and was found in all developmental stages, including eggs, nymphs, and adults. Because BAMH appears to be specific for the SCWL vector, we evaluated it as a candidate for symbiotic control of sugarcane white leaf disease.