Bacillus anthracis Phylogeography: New Clues From Kazakhstan, Central Asia

Abstract

This article describes Bacillus anthracis strains isolated in Kazakhstan since the 1950s until year 2016 from sixty-one independent events associated with anthrax in humans and animals. One hundred and fifty-four strains were first genotyped by Multiple Locus VNTR (variable number of tandem repeats) Analysis (MLVA) using 31 VNTR loci. Thirty-five MLVA31 genotypes were resolved, 28 belong to the A1/TEA group, five to A3/Sterne-Ames group, one to A4/Vollum and one to the B clade. This is the first report of the presence of the B-clade in Kazakhstan. The MLVA31 results and epidemiological data were combined to select a subset of seventy-nine representative strains for draft whole genome sequencing (WGS). Strains from Kazakhstan significantly enrich the known phylogeny of the Ames group polytomy, including the description of a new branch closest to the Texas, United States A.Br.Ames sublineage stricto sensu. Three among the seven currently defined branches in the TEA polytomy are present in Kazakhstan, “Tsiankovskii”, “Heroin”, and “Sanitary Technical Institute (STI)”. In particular, strains from the STI lineage are largely predominant in Kazakhstan and introduce numerous deep branching STI sublineages, demonstrating a high geographic correspondence between “STI” and Kazakhstan, Central Asia. This observation is a strong indication that the TEA polytomy emerged after the last political unification of Asian steppes in the fourteenth century of the Common Era. The phylogenetic analysis of the Kazakhstan data and of currently available WGS data of worldwide origin strengthens our understanding of B. anthracis geographic expansions in the past seven centuries.

New Research on the Bacillus anthracis Genetic Diversity in Siberia

“…Figure 4 shows the Tsiankovskii phylogeny based on the wgSNP data from 33 strains. Four sublineages, labelled L1 to L4, were previously defined [11]. Lineages L1 to L3, derived from the most ancestral nodes, are represented by strains from Bulgaria, Greece, and Albania.…”

“…The most widespread canSNP group is A.Br.008/009, also referred to as TEA (trans-Eurasian), whose strains are present in Eurasia and are very widely represented in Russia [9]. This group is divided into two subgroups: A.Br.008/011 and A.Br.011/009 [10,11]. A.Br.008/011 is a polytomy comprising seven radiating branches.…”

Real-Time PCR Detection of <i>Bacillus anthracis</i> by Lambda_Ba03 Prophage Genes

“…цель [8]. все образцы днк, использованные в исследовании, предварительно протестированы путем амплификации фрагмента 16S рднк (универсальные праймеры 784F и 926R [9]) для подтверждения наличия бактериальной днк.…”

“…для определения чувствительности разработанных наборов праймеров и зондов проведена пцр-рв с положительными контрольными образцами днк изолятов B. anthracis [8]…”