Bulletin de la Société française de microbiologie 03/2009; 24(1):293-301.


Le diagnostic microbiologique s’est longtemps tourné vers la recherche de possibilités d'automatisation des diverses étapes analytiques, de nouvelles technologies appliquées à la problématique bactériologique suggèrent désormais la possibilité de réelles avancées en termes d'unicité des méthodes, de maîtrise des coûts et de rapidité du diagnostic. Parmi les applications récentes de technologies émergentes figure la spectrométrie de masse. Cette technique permet de définir des masses différentes à une précision de 0,2 Da, elle a ainsi une précision moléculaire. Elle peut théoriquement s'appliquer à la définition des êtres vivants. Sa sensibilité en termes de quantité de produits permet de s'intéresser aux microorganismes. Après l'exploration des acides gras et des polyholosides bactériens, ce sont les protéines abondantes ou les petits amplicons d'ADN qui font l'objet des plus grandes attentions pour les applications de la spectrométrie de masse. Nous allons nous attacher dans cette revue à la description de deux systèmes d'identification des bactéries via les protéines ou via de courtes séquences spécifiques d'ADN et la spectrométrie de masse.

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Available from: Moussaoui Wardi, Oct 08, 2015
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    • "Inactivation of bacteria: The bacteria were suspended in 300 lL water and inactivated by the addition of 900 ll ethanol at room temperature. The samples could be stored at room temperature for several days or at 4–8°C for several weeks (Moussaoui et al. 2009). Abundant Proteins extraction: This step was performed at room temperature. "
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    ABSTRACT: A total of 21 isolates of Vibrio cholerae non-O1 strains were isolated from three wastewater treatment plants in Agadir, Morocco. The isolates were analyzed by biochemical analysis, antibiogram, pulsed-field gel electrophoresis and the MALDI-TOF patterns of their protein masses were compared. Over 67% of isolates were susceptible to antimicrobial agents tested and 14% proved resistant to both trimethoprim-sulfamethoxazole and nalidixic acid. Typing by pulsed-field gel electrophoresis with NotI digestion revealed that the V. cholerae non-O1 strains from Agadir (Morocco) have a lower level of genetic homogeneity, the restriction patterns of whole-chromosomal DNA grouped the V. cholerae O1 and V. alginolyticus strains into a separate cluster from V. metschnikovii and V. cholerae non-O1 isolates. Furthermore, to gain additional analytical accuracy and reliability in the analysis we used dendrogram based on MALDI-TOF spectral patterns generated by the BioTyper 1.1™ software. All m/z signatures of all strains tested indicate that the mass spectral data contained sufficient information to distinguish between strains of V. cholerae. KeywordsMALDI-TOF–Pulsed-field gel electrophoresis– Vibrio cholerae –Wastewater
    World Journal of Microbiology and Biotechnology 05/2011; 27(5):1099-1108. DOI:10.1007/s11274-010-0556-7 · 1.78 Impact Factor
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    ABSTRACT: Background: Infections due to Staphylococcus sciuri in hospitalized patients seem to be emerging in different countries. Their incidence and clinical impact with inpatients have not been studied in Benin. Objective: The aim of this study was to estimate the prevalence of Staphylococcus sciuri during bloodstream infection and to assess the importance of the hospital environment as a possible secondary reservoir of multiresistant bacteria capable of colonizing or infecting patients. Patients and methods: Between June and December 2008, clinical information and samples were collected from patients suspected to have nosocomial bloodstream infections at a tertiary hospital in Benin. The isolates were identified, tested for antimicrobial susceptibility. Particularly attention was paid to Staphylococcus sciuri and factors associated with the carriage. Concurrently, swabbing of environment was achieved. MALDI TOF of abundant proteins was applied to identify and to discriminate Staphylococcus sciuri isolates. Results: Nosocomial bactereamia incidence rate was 2, 58 cases per 1000 patient-days. The proportion of Staphylococcus sciuri among coagulase negative staphylococci was 24.5% and represented 15% of the environment specimens. Catheter was the commonest source of nosocomial bacteremia (41%). The frequency of resistance to methicillin for Staphylococcus aureus isolates was 36% and 44% for Staphylococcus sciuri isolates. Mass spectra were specific for five groups of S. sciuri isolates. Conclusion: Our survey revealed a high level of Staphylococcus sciuri among Coagulase Negative Staphylococcus isolated from blood specimen. There is a need to institute strict hospital infection control policy and a regular surveillance of resistance to antimicrobial agents.