1 PLoS ONE 2011 Vol: 6(1):. DOI: 10.1371/journal.pone.0015731

Characterization of Burkholderia rhizoxinica and B. endofungorum Isolated from Clinical Specimens

Eight isolates submitted to CDC from 1989 to 2006 from clinical specimens were initially identified as members of the genus Burkholderia based on preliminary cellular fatty acid analysis and/or 16S rRNA gene sequencing. With the recent descriptions of the new species B. rhizoxinica and B. endofungorum, which are considered endosymbiotic bacteria in Rhizopus microsporus fungi, we now identify seven of these clinical isolates as B. rhizoxinica and one as B. endofungorum based on biochemical testing, 16s rRNA, and DNA-DNA hybridization results. We also further characterize these isolates by assessing toxin production and/or by multiple locus sequence typing.

Mentions
Figures
Figure 1: MEGA 3 analysis of 16S rRNA gene sequences using neighbor-joining and Kimura 2-parameter settings with 1000 step bootstrap.          Phylogenetic tree of Burkholderia rhizoxinica and B. endofungorum based on comparisons with 16S rDNA sequences of related bacteria. Pseudomonas aeruginosa DSM 50071 (GenBank accession no. X06684) was used as an outgroup for this analysis. Bar, 2% sequence dissimilarity. Figure 2: Phylogenetic network of Burkholderia spp from. clinical isolates together with fungal symbionts (B1–B8) based on MLST data.          B1: Burkholderia rhizoxinica type strain. B5: B. endofungorum type strain. BPS: B. pseudomallei (outgroup). Figure 3: HPLC profiles of culture extracts of strains H2199 (A) and G7344 (B) showing the production of various antimitotic rhizoxin derivatives.
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References
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