0000000001052700
AUTHOR
Elodie Barbier
First molecular detection of mycobacterium bovis in environmental samples from a French region with endemic bovine tuberculosis
Aims The aim of the study was to determine the prevalence of Mycobacterium bovis (the causative agent of bovine tuberculosis, bTB) in environmental matrices within a French region (Cote d'Or) affected by this zoonotic disease. Methods and Results We report here the development and the use of molecular detection assays based on qPCR (double fluorescent dye labelled probe) to monitor the occurrence of Mycobacterium tuberculosis complex (MTBC) or M. bovis in environmental samples collected in pastures where infected cattle and wildlife had been reported. Three qPCR assays targeting members of the MTBC (IS1561’ and Rv3866 loci) or M. bovis (RD4 locus) were developed or refined from existing ass…
New insights into the use of rhizobia to mitigate soil N2O emissions
Agriculture is a major anthropogenic source of the greenhouse gas N2O, which is also involved in stratospheric ozone depletion. While the use of rhizobial inoculants has already been reported as an emerging option for mitigating soil N2O emissions, this study presents an in situ abatement of 70% of soil N2O emission using the strain nosZ+ G49 vs. nosZ− USDA138 in association with soybean. Therefore, we consider that the choice of the inoculant strain of a leguminous crop should take into account the capacity of strains to reduce nitrous oxide in addition to their N fixation capacity. This study also clearly suggests that this mitigation option could be considered not only for soybean but al…
Development of a database for the rapid and accurate routine identification of Achromobacter species by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS).
International audience; Objectives: Achromobacter spp. are emerging pathogens in respiratory samples from cystic fibrosis patients. The current reference methods (nrdA-sequencing or multilocus sequence typing) can identify 18 species which are often misidentified by conventional techniques as A. xylosoxidans. A few studies have suggested that matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) provides accurate identification of the genus but not of species. The aims of this study were (a) to generate a database for MALDI-TOF/MS Bruker including the 18 species, (b) to evaluate the suitability of the database for routine laboratory identification, and …
Rapid dissemination of Mycobacterium bovis from cattle dung to soil by the earthworm Lumbricus terrestris
International audience; Indirect transmission of Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), between wildlife and livestock is thought to occur by inhalation or ingestion of environmental substrates contaminated through animal shedding. The role of the soil fauna, such as earthworms, in the circulation of M. bovis from contaminated animal feces is of interest in the epidemiology of bTB. The objective of this study was to assess the impact of earthworm activity on M. bovis transfer from animal dung to castings and the surrounding soil. For this purpose, microcosms of soil containing the anecic eathworms Lumbricus terrestris were prepared and covered with cattle fec…
Impact of temperature and soil type on Mycobacterium bovis survival in the environment
Mycobacterium bovis, the causative agent of the bovine tuberculosis (bTB), mainly affects cattle, its natural reservoir, but also a wide range of domestic and wild mammals. Besides direct transmission via contaminated aerosols, indirect transmission of the M. bovis between wildlife and livestock might occur by inhalation or ingestion of environmental substrates contaminated through infected animal shedding. We monitored the survival of M. bovis in two soil samples chosen for their contrasted physical and-chemical properties (i.e. pH, clay content). The population of M. bovis spiked in sterile soils was enumerated by a culture-based method after 14, 30, 60, 90, 120 and 150 days of incubation…
Development of phylogroup-specific taqman real-time assays for identification of members of klebsiella pneumoniae complex
International audience; • Klebsiella Klebsiellapneumoniae pneumoniae pneumoniae (Kp )represents agrowinggrowing public publichealth concern due to the emergence emergence of multidrug multidrug multidrug resistance resistance and andhypervirulence hypervirulence . • The Kp species complex complex includes includes 7closely related related phylogroups :Klebsiella Klebsiellapneumoniae (phylogroup (phylogroup Kp 1), K.quasipneumoniae quasipneumoniae quasipneumoniae subsp .quasipneumoniae quasipneumoniae (Kp 2)and subsp .similipneumoniae similipneumoniae similipneumoniae similipneumoniae similipneumoniae (Kp 4), K.variicola variicola subsp .variicola variicola variicola(Kp 3)and subsp .tropical…
Prevalence of Mycobacterium bovis in agroecosystems : analysis of potential environmental reservoirs (soil, fresh water, soil fauna and aquatic fauna) and circulation of the bacteria between the different environmental compartments
Bovine tuberculosis is an infectious disease caused by Mycobacterium bovis. This disease affects cattle, and many species of domestic and wild mammals, and humans. The circulation of the bacteria in various multi-host systems promotes the maintenance of the disease and the contamination of cattle in the vicinity. Beside direct transmission of the bacteria through the respiratory route, indirect transmission, through inhalation or ingestion of environmental matrices contaminated by an infected animal excretory, is suspected in several countries. Environmental contamination with M. bovis appears to be a crucial factor in the persistence of the infection in multi-host systems.In Côte d'Or, a F…
Caractérisation génotypique et le phénotypique de souches de Rhizobia par rapport à leur capacité à réduire le protoxyde d’azote (N2O), puissant gaz à effet de serre
Rapport de Stage de Master 2 EA MERS CT3; Master
Prevalence of Mycobacterium bovis in agroecosystems : analysis of potential environmental reservoirs (soil, fresh water, soil fauna and aquatic fauna) and circulation of the bacteria between the different environmental compartments
Bovine tuberculosis is an infectious disease caused by Mycobacterium bovis. This disease affects cattle, and many species of domestic and wild mammals, and humans. The circulation of the bacteria in various multi-host systems promotes the maintenance of the disease and the contamination of cattle in the vicinity. Beside direct transmission of the bacteria through the respiratory route, indirect transmission, through inhalation or ingestion of environmental matrices contaminated by an infected animal excretory, is suspected in several countries. Environmental contamination with M. bovis appears to be a crucial factor in the persistence of the infection in multi-host systems. In Côte d'Or, a …