Multiple-locus sequence typing analysis of Bacillus thuringiensis recovered from the phylloplane of clover (Trifolium hybridum) in vegetative form.
Abstract The chromosomal genotype, as judged by multi locus sequence typing, and the episomal genotype, as judged by plasmid profile and cry gene content, were analyzed for a collection of strains of Bacillus thuringiensis. These had been recovered in vegetative form over a period of several months from the leaves of a small plot of clover (Trifolium hybridum). A clonal population structure was indicated, although greater variation in sequence types (STs) was discovered than in previous collections of B. cereus/B. thuringiensis. Isolates taken at the same time had quite different genotypes, whereas those of identical genotypes were recovered at different times. The profiles of plasmid content and cry genes generally bore no relation to each other nor to the STs. Evidently, although relatively little recombination was occurring in the seven chromosomal genes analyzed, a great deal of conjugal transfer, and perhaps recombination, was occurring involving plasmids. A clinical diarrheal isolate of B. cereus and the commercial biopesticide strain HD-1 of B. thuringiensis, both included as out-groups, were found to have very similar STs. This further emphasizes the role of episomal elements in the characteristics and differentiation of these two species.
School of Science, University of Greenwich, Chatham Maritime ME4 4TB, UK.
M F
MF
Bizzarri
A
A
Prabhakar
A H
AH
Bishop
D001413:Bacillus thuringiensis / Q000145:classification / Q000235:genetics*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D002876:Chromosomes, Bacterial / Q000235:genetics; D003227:Conjugation, Genetic; D004269:DNA, Bacterial / Q000235:genetics; D017753:Ecosystem; D004731:Endotoxins / Q000235:genetics; D005798:Genes, Bacterial; D005838:Genotype; D006460:Hemolysin Proteins / Q000235:genetics; D015810:Linkage Disequilibrium; D018515:Plant Leaves / Q000382:microbiology*; D010957:Plasmids; D029921:Trifolium / Q000382:microbiology*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis