Identificação e caracterização de rnas não codificadores em isolados de bacillus thuringiensis (Bacillus cereus sensu lato) por sequenciamento do conjunto de pequenos RNAs

Abstract

The Bacillus cereus group aggregates eight bacterial species that are closely related to each other, however, their phylogenetic and taxonomic relationships are still debated. The Bacillus anthracis, Bacillus cereus and Bacillus thuringiensis are the three main species in the cereus group. There is a close genomic similarity between these three bacteria, which leads to the proposal that they can be considered as the same species. The distinction between species of the B. cereus group is essentially attributed to phenotypic characteristics and pathogenic properties, whose genes encoding them, have much of their specificities attributed to their plasmids. Despite the similarity, they are phenotypically distinct and have important particularities. B. anthracis is a pathogen for humans and other animals, B. cereus is an important food contaminant and B. thuringiensis is the most used bacterium in the biological control of pests and disease vectors. Thus, this work aims to contribute to the clarification on the genetic proximity between these three constituents of the Bacillus cereus sensu lato group through the identification and characterization of non-coding RNAs in the species of B. thuringiensis, through the identification and characterization of noncoding RNAs in the lineage Bacillus thuringiensis bt407, adding the identification and characterization of homologous sequences in the Rfam database. The methodology proposed in this work allowed the identification of a total of 355 candidate sequences for ncRNAs distributed in 49 families. With the removal of common RNAs (tRNA, tmRNA, 58s_RNA and 5s_RNA), the methodology identified 223 sequences distributed in 45 families. The present work also presents a comparison of the proposed ncRNAS search methodology with other search methods carried out by other authors for Bacillus thuringiensis strain Bt407.