Search

This is the first report of a Corynebacterium (C) ulcerans-infection in European roe deer (Capreolus capreolus). The bacterium was isolated from a grapefruit sized abscess of an animal that had been shot. In addition to biochemical tests, the isolate was identified by Fourier transform infrared spectroscopy (FT-IR) and partial sequencing of the rpoB gene. The isolated bacteria showed phospholipase D activity that could be demonstrated by reverse CAMP-test. A tox-gene could be detected by PCR but the Elek-test specific for diphtheria toxin failed.The isolate was compared to two C. ulcerans-strains isolated from wild boar (Sus scrofa) from the state of Baden-Wuerttemberg described recently.

Pathogenic Bacillus cereus (B. cereus) cause two types of foodborne diseases: the diarrhoeal type and, after production of a heat stable toxin called cereulide, an emetic type. The identification of B. cereus in official food monitoring has been traditionally performed using the cultural procedure as described in method 00.00-25 according to section 64 of the German Food and Feed Law (LFGB). Strains isolated by this method are called "presumptive B. cereus" a collective name for B. cereus sensu strictu, B. thuringiensis and closely related Bacilli. Some potentially pathogenic thermotolerant isolates ("B. cytotoxicus") are not covered by this method. In this work Fourier-Transform-infrared spectroscopy (FT-IR) in combination with artificial neural network based data analysis was tested and verified for the further differentiation of "presumptive B. cereus" isolates and closely related Bacilli. For this purpose 122 Bacillus strains were, in addition to the section 64 LFGB method, assayed for formation of parasporal crystals, thermotolerant growth, PCR and LC-MS/MS. Based on this data a further FT-IR-method was developed for the differentiation of emetic B. cereus. Exemplarily, these methods were applied in a B. cereus related foodborne outbreak. In addition, the obtained FT-IR-spectra visualize the chain of infection.

The identification of thermotolerant campylobacters in official food control in the state of Baden-Wuerttemberg has been traditionally performed using the cultural procedure as described in the ISO-Norm 10272:1995. Analysis thus took 5-6 days to complete. Additionally diagnostic problems caused by the accompanying flora as well as the resistance to nalidixic acid occured. Within the scope of this study these problems could be solved by introducing a filtration step for the reduction of the accompanying flora and by performing the indoxyl acetate-hydrolysis-test in addition to the antibiotic-resistance-test. Besides various PCR protocols for the identification of thermotolerant campylobacters from food were established as an alternative to the cultural procedure, providing reliable results within two days. Furthermore, infrared spectroscopy was tested for the identification of Campylobacter isolates. Using this technique and with the help of a suitable data base, bacterial pure cultures can be differentiated within 2 hours. Among others 356 samples of raw poultry meat were tested with the newly established procedures as well as with the classical cultural method, showing that 32% of the samples were Campylobacter spp. positive. 37% of these isolates were resistant against nalidixic acid. This indicates that the development of resistances in Campylobacter spp. in Germany follows the same trend described for other European countries.