Fourier transform infrared spectroscopy of DNA from Borrelia burgdorferi sensu lato and Ixodes ricinus ticks

• Structural characteristics of DNA from Borrelia burgdorferi sensu lato strains.
• Structural characteristics of DNA from positive and negative Ixodes ricinus ticks.
• The predominant DNA conformation has been found to be the B-form.
• FT-IR signatures of DNA from Borrelia burgdorferi sensu stricto with antibiotics.
• Spectral differences between DNAs from motile bacterial cells and immotile spirochetes.

In this work we present a method for detection of motile and immotile Borrelia burgdorferi genomic DNA, in relation with infectious and noninfectious spirochetes. An FT-IR study of DNA isolated from B. burgdorferi sensu lato strains and from positive and negative Ixodes ricinus ticks, respectively, is reported. Motile bacterial cells from the species B. burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii were of interest. Also, FT-IR absorbance spectra of DNA from immotile spirochetes of B. burgdorferi sensu stricto, in the absence and presence of different antibiotics (doxycycline, erythromycin, gentamicin, penicillin V or phenoxymethylpenicillin, tetracycline, respectively) were investigated.FT-IR spectra, providing a high molecular structural information, have been analyzed in the wavenumber range 400–1800 cm−1. FT-IR signatures, spectroscopic band assignments and structural interpretations of these DNAs are reported.Spectral differences between FT-IR absorbances of DNAs from motile bacterial cells and immotile spirochetes, respectively, have been found. Particularly, alterations of the sugar-phosphate B-form chain in the case of DNA from Borrelia immotile cells, as compared with DNA from B. burgdorferi sensu lato motile cells have been observed.Based on this work, specific B. burgdorferi sensu lato and I. ricinus DNA-ligand interactions, respectively, might be further investigated using Fourier transform infrared spectroscopy.

Characterization of DNA from Borrelia burgdorferi sensu lato and Ixodes ricinus ticks, respectively, was undertaken by use of FT-IR spectroscopy. Motile bacterial cells from the species Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii were under study. Also, FT-IR absorbance spectra of DNA extracted from immotile spirochetes of Borrelia burgdorferi sensu stricto, in the absence and presence of different antibiotics were reported.Figure optionsDownload as PowerPoint slide