Análises ômicas de Bacillus spp. isolados de ecossistemas amazônicos ativos para o controle de Aedes aegypti

Abstract

The Aedes aegypti mosquito is the primary vector of arboviruses such as dengue, Zika, yellow fever, and chikungunya, representing a serious public health problem. Biological control, particularly the use of Bacillus thuringiensis (Bt), is a widely used alternative. Environmental factors can reduce the effectiveness of biolarvicides, and studies indicate resistance of mosquitoes to some of them. Thus, the search for new entomopathogenic agents, especially from environmental sources, is essential. The Amazon, with its rich microbial biodiversity, offers significant unexplored potential, and advances in molecular techniques, combined with bioinformatics tools and omics approaches, have expanded the possibilities for the investigation and application of these microorganisms. This study aimed to characterize the Amazonian B. thuringiensis GD02.13 strain and evaluate its larvicidal potential against the Aedes aegypti mosquito, the main vector of arboviruses such as dengue, Zika, and chikungunya. The Amazonian B. thuringiensis GD02.13 strain was characterized, focusing on its larvicidal potential against Aedes aegypti. The strain was isolated from the Amazon region and identified as B. thuringiensis through phylogenetic analysis based on 443 orthologous genes. Its genome, of 6.6 Mb, revealed genes encoding insecticidal toxins and 16 biosynthetic gene clusters for secondary metabolites. Bioassays with purified spores and crystals at different concentrations (0.1–0.4 µg/mL) showed 100% larval mortality, outperforming the commercial strain Bti AM65-52. CCD analysis identified phenolic compounds, alkaloids, and terpenes in bacterial extracts. Proteomic characterization through SDS-PAGE and LC-MS/MS revealed Cry4Aa, Cry4Ba, Cry11Aa, and Cyt1Aa toxins, as well as proteins related to virulence and resistance. Based on these results, the GD02.13 strain of B. thuringiensis demonstrates significant biotechnological potential as a source of effective natural bioinsecticides, reinforcing its applicability in vector control of disease-transmitting mosquitoes. Therefore, the data obtained in this study support the development of new insecticidal products based on the GD02.13 B. thuringiensis strain.