Bto_UNVM, a novel Bacillus toyonensis strain showing an extraordinary insecticidal-like gene repertory

SAUKA, D.; FERNÁNDEZ-GÖBEL, T.; OCAMPO, F.; BERRY, C.; DEL VALLE, E.; PALMA, L.

Nelson Mandela Bay

Congreso; International Congress on Invertebrate Pathology and Microbial Control and 54th Annual Meeting of the Society for Invertebrate Pathology; 2022

Society for Invertebrate Pathology

Bacillus thuringiensis (Bt) is a gram-positive bacterium producing parasporal crystal proteins with insecticidal activity against insects and nematodes. Beyond Bt, other gram-positive bacterial species have been described for showing insecticidal activity, namely Lysinibacillus sphaericus, Paenibacillus spp. and Brevibacillus laterosporus. In addition, a novel Bacillus toyonensis strain has been recently described to produce parasporal crystals with insecticidal activity, that wasdesignated Bacillus toyonensis biovar Thuringiensis. In this study we report the isolation and characterization of another B. toyonensis strain producing parasporal crystals. The strain was isolated from a soil sample obtained from a native ecosystem and presented the typical Bt morphology in nutrient agar plates. The parasporal crystals were produced abundantly asobserved under the light microscopy which were later confirmed using Scanning Electron Microscopy. The genome sequence was obtained and assembled into 182 contigs with a total genomic size of 6,228,799 bp and 35 % G+C. The genome analysis performed with the Type (Strain) Genome Server showed that this strain belongs to B. toyonensis species. Its genome sequenceharbors eight coding sequences showing homology with Cyt1Aa1, Cry1Cb3, Cry32Qa1, Cry32Pa1, Cry3Aa1, Cry32Ua1, Cry32Ka1 and Cry32Fa1 proteins. In order to determine the biocidal activity of this novel strain, bioassays will be conducted with Aedes aegypti (Dipera: Culicidae), Cydia pomonella (Lepidoptera: Tortricidae), Alphitobius diaperinus (Coleoptera: Tenebrionidae) andPanagrellus redivivus (Nematoda: Panagrolaimidae).