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Prague, Czech Republic

Hubert J.,Czech Republic Crop Research Institute | Hubert J.,Medical Center Prague | Kopecky J.,Czech Republic Crop Research Institute | Perotti M.A.,University of Reading | And 5 more authors.
Microbial Ecology

Internal bacterial communities of synanthropic mites Acarus siro, Dermatophagoides farinae, Lepidoglyphus destructor, and Tyrophagus putrescentiae (Acari: Astigmata) were analyzed by culturing and culture-independent approaches from specimens obtained from laboratory colonies. Homogenates of surface-sterilized mites were used for cultivation on non-selective agar and DNA extraction. Isolated bacteria were identified by sequencing of the 16S rRNA gene. PCR amplified 16S rRNA genes were analyzed by terminal restriction fragment length polymorphism analysis (T-RFLP) and cloning sequencing. Fluorescence in situ hybridization using universal bacterial probes was used for direct bacterial localization. T-RFLP analysis of 16S rRNA gene revealed distinct species-specific bacterial communities. The results were further confirmed by cloning and sequencing (284 clones). L. destructor and D. farinae showed more diverse communities then A. siro and T. putrescentiae. In the cultivated part of the community, the mean CFUs from four mite species ranged from 5. 2 × 102 to 1. 4 × 103 per mite. D. farinae had significantly higher CFUs than the other species. Bacteria were located in the digestive and reproductive tract, parenchymatical tissue, and in bacteriocytes. Among the clones, Bartonella-like bacteria occurring in A. siro and T. putresecentiae represented a distinct group related to Bartonellaceae and to Bartonella-like symbionts of ants. The clones of high similarity to Xenorhabdus cabanillasii were found in L. destructor and D. farinae, and one clone related to Photorhabdus temperata in A. siro. Members of Sphingobacteriales cloned from D. farinae and A. siro clustered with the sequences of "Candidatus Cardinium hertigii" and as a separate novel cluster. © 2011 Springer Science+Business Media, LLC. Source

Klubal R.,Medical Center Prague | Kopecky J.,Czech Republic Crop Research Institute | Nesvorna M.,Czech Republic Crop Research Institute | Sparagano O.A.E.,Coventry University | And 3 more authors.
Experimental and Applied Acarology

Bacteria associated with the tick Ixodes ricinus were assessed in specimens unattached or attached to the skin of cats, dogs and humans, collected in the Czech Republic. The bacteria were detected by PCR in 97 of 142 pooled samples including 204 ticks, i.e. 1–7 ticks per sample, collected at the same time from one host. A fragment of the bacterial 16S rRNA gene was amplified, cloned and sequenced from 32 randomly selected samples. The most frequent sequences were those related to Candidatus Midichloria midichlori (71 % of cloned sequences), followed by Diplorickettsia (13 %), Spiroplasma (3 %), Rickettsia (3 %), Pasteurella (3 %), Morganella (3 %), Pseudomonas (2 %), Bacillus (1 %), Methylobacterium (1 %) and Phyllobacterium (1 %). The phylogenetic analysis of Spiroplasma 16S rRNA gene sequences showed two groups related to Spiroplasma eriocheiris and Spiroplasma melliferum, respectively. Using group-specific primers, the following potentially pathogenic bacteria were detected: Borellia (in 20 % of the 142 samples), Rickettsia (12 %), Spiroplasma (5 %), Diplorickettsia (5 %) and Anaplasma (2 %). In total, 68 % of I. ricinus samples (97/142) contained detectable bacteria and 13 % contained two or more putative pathogenic groups. The prevalence of tick-borne bacteria was similar to the observations in other European countries. © 2015, Springer International Publishing Switzerland. Source

Erban T.,Czech Republic Crop Research Institute | Erban T.,Medical Center Prague | Hubert J.,Czech Republic Crop Research Institute | Hubert J.,Medical Center Prague
Archives of Insect Biochemistry and Physiology

The ingestion of chromogenic or fluorescent substrates for protease detection enables the visualization of digestive processes in mites in vivo due to their transparent bodies. The substrates for protease detection were offered to Lepidoglyphus destructor, and the resulting signals were observed in specimens under a compound microscope. The protease activity was successfully localized using chromogenic substrates (azoalbumin, AAPpNA, SAAPFpNA, elastin-orcein, SA 3pNA, ZRRpNA, ArgpNA, and MAAPMpNA) and fluorescent substrates (casein-fluorescein, albumin-fluorescein, AAPAMC, BAAMC, ZRRAMC, ArgAMC, and AGPPPAMC). No activity was detected using the keratin azure and BApNA substrates. In the mesodeum, trypsin-like activity generated by hydrolysis of the BApNA substrate was not observed, but the BAAMC substrate allowed the visualization of trypsin-like activity in food boli in the posterior mesodeum. The results indicate that cathepsins B, D, and G and cathepsin H or aminopeptidase-like activities are present in the midgut of L. destructor. Among these activities, cathepsin D-like activity was identified for the first time in the gut of L. destructor. All proteases mentioned are produced in the mesodeal lumen and form the food bolus together with ingested food, afterward passing through the gut to be defecated. The method used enables the visualization of protease activities in the gut of transparent animals. © 2011 Wiley Periodicals, Inc. © 2011 Wiley-Liss, Inc. Source

Rahel J.,Masaryk University | Jonasova E.,Masaryk University | Nesvorna M.,Czech Republic Crop Research Institute | Klubal R.,Medical Center Prague | And 2 more authors.
Pest Management Science

Background: Plasma treatment enables effective binding of chitosan film to textile fibres. Heavy metal ions such as Ag+ adsorbed onto the chitosan coating are known to enhance toxicity to microorganisms. The acaricidal effect of chitosan and chitosan/metal adducts with Ag+, Zn2+ and Cu2+ was tested in laboratory experiments. Tested species Acarus siro, Dermatophagoides farinae, D. pteronyssinus and Tyrophagus putrescentiae are allergen producers and important pests in house dust, stored food and feed. The mortality was compared after 24 h of exposure of mites to plasma-treated textiles. Results: Chitosan/Ag+ textile caused at least 80% mortality of all species tested. Chitosan/Zn2+ and chitosan/Cu2+ textiles had a smaller effect on mite mortality than chitosan/Ag+. The conversion of chitosan/Ag+ finishing to chitosan/Ag2O did not influence the mortality of mites in biotests, except that of Tyrophagus putrescentiae, where the mortality decreased from 86 to 64%. Conclusion: The results support a great potential of chitosan/Ag+ fibres in acaricidal materials and/or mite protective food packages. © 2012 Society of Chemical Industry. Source

Hubert J.,Czech Republic Crop Research Institute | Hubert J.,Medical Center Prague | Nesvorna M.,Czech Republic Crop Research Institute | Klubal R.,Medical Center Prague | Stejskal V.,Czech Republic Crop Research Institute
International Journal of Acarology

Chlorfenapyr is a pesticide that is widely used to control herbivorous mites and insects. The commercial application of chlorfenapyr is focused on the control of urban pests (cockroaches, bed bugs and ants), but the toxicity of chlorfenapyr to domestic mites is poorly understood. Here, the toxic effect of chlorfenapyr to domestic mites was tested in an impregnated filter paper laboratory test. Chlorfenapyr, either as an analytic standard or commercial suspension concentrate (SC) formulation, was applied to the glass bottles with filter paper, and the mortality of the mites (Acarus siro, Lepidoglyphus destructor, Dermatophagoides pteronyssinus and D. farinae) was evaluated after 24 h of exposure. There were no significant differences in the toxicity to the mites between the SC and the analytical standard. The chlorfenapyr in both formulations was toxic to L. destructor and D. pteronyssinus, D. farinae. The LC95 ranged from 20 to 304 g cm-2. Lower toxicity was observed with A. siro, and LC values were not estimated. © 2013 Taylor & Francis. Source

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