Phylogenetic relationships among Bacillus thuringiensis (Bacillaceae: Bacillales) strains based on a comparison of SSU rRNA sequences and genome profiling

• Published in: Applied entomology and zoology Vol. 46; no. 4; pp. 489 - 496
• Main Authors: Oda, Hisayuki, Hatakeyama, Yoshinori, Iwano, Hidetoshi
• Format: Journal Article
• Language: English
• Published: Japan Springer Japan 01.11.2011
• Subjects: Agriculture; Applied Ecology; Bacillaceae; Bacillus cereus; Bacillus thuringiensis; Biomedical and Life Sciences; Entomology; Environmental Management; Evolution; Flagella; Gel electrophoresis; Genomes; Homology; Life Sciences; Original Research Paper; Phylogeny; Plant Pathology; Polymerase chain reaction; rRNA; Serotypes; Serotyping; Temperature effects; Zoology; Phylogenetic relationship; SSU rRNA sequence; Genome profiling
• ISSN: 0003-6862; 1347-605X
• DOI: 10.1007/s13355-011-0068-4

Bacillus thuringiensis Berliner has previously been classified via the serological identification of flagellar antigens. However, the phylogenetic relationships among strains of B. thuringiensis cannot be investigated by serotyping. Furthermore, high levels of homology have been found in gene sequences among various strains, complicating the determination of their evolutionary relationships. In order to elucidate the phylogenetic relationships within B. thuringiensis , we analyzed 40 strains belonging to typical serotypes using two approaches: an analysis of small subunit (SSU) rRNA sequences and genome profiling (GP) based on temperature gradient gel electrophoresis of random PCR products. The SSU rRNA analysis resulted in all 40 strains forming a single cluster with Bacillus cereus Frankland & Frankland. The distances among the subclusters were too small to further classify the strains. On the other hand, the phylogenetic analysis based on GP resulted in three clusters of B. thuringiensis strains. These results suggest that GP is a better method for the determination of phylogenetic relationships within B. thuringiensis .