title: Phylogenetic Analysis of Pasteuria penetrans by 16S rRNA Gene Cloning and Sequencing.
abstract: Pasteuria penetrans is an endospore-forming bacterial parasite of Meloidogyne spp. This organism is among the most promising agents for the biological control of root-knot nematodes. In order to establish the phylogenetic position of this species relative to other endospore-forming bacteria, the 16S ribosomal genes from two isolates of P. penetrans, P-20, which preferentially infects M. arenaria race 1, and P-100, which preferentially infects M. incognita and M. javanica, were PCR-amplified from a purified endospore extraction. Universal primers for the 16S rRNA gene were used to amplify DNA which was cloned, and a nucleotide sequence was obtained for 92% of the gene (1,390 base pairs) encoding the 16S rDNA from each isolate. Comparison of both isolates showed identical sequences that were compared to 16S rDNA sequences of 30 other endospore-forming bacteria obtained from GenBank. Parsimony analyses indicated that P. penetrans is a species within a clade that includes Alicyclobacillus acidocaldarius, A. cycloheptanicus, Sulfobacillus sp., Bacillus tusciae, B. schlegelii, and P. ramosa. Its closest neighbor is P. ramosa, a parasite of Daphnia spp. (water fleas). This study provided a genomic basis for the relationship of species assigned to the genus Pasteuria, and for comparison of species that are parasites of different phytopathogenic nematodes.
authors.forename: J M
authors.initials: JM
authors.lastname: Anderson
authors.forename: J F
authors.initials: JF
authors.lastname: Preston
authors.forename: D W
authors.initials: DW
authors.lastname: Dickson
authors.forename: T E
authors.initials: TE
authors.lastname: Hewlett
authors.forename: N H
authors.initials: NH
authors.lastname: Williams
authors.forename: J E
authors.initials: JE
authors.lastname: Maruniak