Sequence Variability of pXO1-Located Pathogenicity Genes of Bacillus anthracis Natural Strains of Different Geographic Origin

Abstract

The main pathogenic factor of Bacillus anthracis is a three-component toxin encoded by the pagA, lef, and cya genes, which are located on the pXO1 plasmid. The atxA gene, which encodes the primary regulator of pathogenicity factor expression, is located on the same plasmid. In this work, we evaluated the polymorphism of the pagA, lef, cya, and atxA genes for 85 B. anthracis strains from different evolutionary lineages and canSNP groups. We have found a strong correlation of 19 genotypes with the main evolutionary lineages, but the correlation with the canSNP group of the strain was not as strong. We have detected several genetic markers indicating the geographical origin of the strains, for example, their source from the steppe zone of the former USSR. We also found that strains of the B.Br.001/002 group caused an anthrax epidemic in Russia in 2016 and strains isolated during paleontological excavations in the Russian Arctic have the same genotype as the strains of the B.Br.CNEVA group circulating in Central Europe. This data could testify in favor of the genetic relationship of these two groups of strains and hypothesize the ways of distribution of their ancestral forms between Europe and the Arctic.

New Research on the Bacillus anthracis Genetic Diversity in Siberia

“…Seventeen loci compatible with agarose-gel typing given their repeat unit and overall allele size were used: vrrA, vrrB1, vrrB2, vrrC2, bams01, bams03, bams05, bams21, bams22, bams23, bams24, bams25, bams28, bams34, bams44, bams51, and VNTR23. We also used the bi-allelic locus VNTRacpA, which differentiates lineages A (3 repeat units) and B (4 repeat units) [30,31]. Monoplex PCR products and a 20 bp ladder (Bio-Rad, Hercules, CA, USA) were electrophoresed at 100 V for four hours on a 32 cm length 3% agarose gel prepared in 0.5× TBE.…”

Effect of Lyoprotective Agents on the Preservation of Survival of a Bacillus cereus Strain PBG in the Freeze-Drying Process

“…On the other hand, genes encoding Cry proteins were not found [71], excluding Bacillus thuringiensis. Genes pagA, lef, and cya were also absent [72], eliminating the possibility of B. anthracis. Therefore, based on a more comprehensive molecular characterization that encompasses the identification of specific genes, taxonomic analysis, and microscopic features, such as the presence of Gram-positive bacilli forming endospores and the biochemical properties of the PBC strain, we can conclusively affirm its classification within the species Bacillus cereus.…”

<i>In silico</i> analysis of genomes of Bacillus anthracis strains belonging to major genetic lineages

“…Эти данные получены в экспериментах с внесением мутаций в описанные гены и оценкой их влияния на вирулентность мутантных штаммов в сравнении со штаммами дикого типа. Аллельный полиморфизм для гена ПА, имеющего 6 аллельных типов у природных штаммов дикого типа [20], описан и для других генов факторов патогенности [21][22][23]. Однако вариабельность хромосомных генов, кодирующих продукты, для которых установлено или предполагается влияние на вирулентность B. anthracis, остается не изученной.…”