Fluorescence in situ hybridization using peptide nucleic acid probes for rapid detection of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. paratuberculosis in potable-water biofilms.

Environmental Healthcare Unit, School of Biological Sciences, University of Southampton, Southampton SO16 7PX, United Kingdom.
Applied and Environmental Microbiology (Impact Factor: 3.95). 02/2006; 72(1):848-53. DOI: 10.1128/AEM.72.1.848-853.2006
Source: PubMed

ABSTRACT Here, we present for the first time a high-affinity peptide nucleic acid (PNA) oligonucleotide sequence for detecting Mycobacterium avium bacteria, including the opportunistically pathogenic subspecies M. avium subsp. avium, M. avium subsp. paratuberculosis, and M. avium subsp. silvaticum, by the fluorescence in situ hybridization (FISH) method. There is evidence that M. avium subsp. avium especially is able to survive and grow in drinking-water biofilms and possibly transmit via drinking water. The designed PNA probe (MAV148) specificity was tested with several bacterial species, including other mycobacteria and mycolic acid-containing bacteria. From the range of bacterial strains tested, only M. avium subsp. avium and M. avium subsp. paratuberculosis strains were hybridized. The PNA FISH method was applied successfully to detect M. avium subsp. avium spiked in water samples and biofilm established within a Propella biofilm reactor fed with potable water from a distribution supply.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The development of biofilms in drinking water distribution systems (DWDS) can cause pipe degradation, changes in the water organoleptic properties but the main problem is related to the public health. Biofilms are the main responsible for the microbial presence in drinking water (DW) and can be reservoirs for pathogens. Therefore, the understanding of the mechanisms underlying biofilm formation and behavior is of utmost importance in order to create effective control strategies. As the study of biofilms in real DWDS is difficult, several devices have been developed. These devices allow biofilm formation under controlled conditions of physical (flow velocity, shear stress, temperature, type of pipe material, etc), chemical (type and amount of nutrients, type of disinfectant and residuals, organic and inorganic particles, ions, etc) and biological (composition of microbial community - type of microorganism and characteristics) parameters, ensuring that the operational conditions are similar as possible to the DWDS conditions in order to achieve results that can be applied to the real scenarios. The devices used in DW biofilm studies can be divided essentially in two groups, those usually applied in situ and the bench top laboratorial reactors. The selection of a device should be obviously in accordance with the aim of the study and its advantages and limitations should be evaluated to obtain reproducible results that can be transposed into the reality of the DWDS. The aim of this review is to provide an overview on the main reactors used in DW biofilm studies, describing their characteristics and applications, taking into account their main advantages and limitations.
    Water Research 06/2014; 62C:63-87. · 5.32 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Mycobacterioses in animals cause economical losses and certain Mycobacterium avium subspecies are regarded as potential zoonotic agents. The evaluation of the zoonotic risk caused by M. avium subspecies requires information about the quantities of Mycobacterium strains in infected animals. Because M. avium subspecies in pig tissues are difficult or even impossible to quantify by culturing, we tested the suitability of a culture-independent real-time quantitative PCR (qPCR) assay for this purpose. METHODS: Mycobacterial DNA was extracted from porcine tissues by a novel method and quantified by Mycobacterium genus specific qPCR assay targeting the 16S rRNA gene. RESULTS: The response of the qPCR assay to the amount of M. avium subspecies avium mixed with porcine liver was linear in the range of approximately log105 to log107 Mycobacterium cells per 1 g of liver. The assay was validated with three other M. avium subspecies strains. When the assay was applied to porcine lymph nodes with or without visible lesions related to Mycobacterium avium subspecies infections, around 104--107 mycobacterial genomes per gram of lymph nodes were detected. CONCLUSIONS: The qPCR assay was found to be suitable for the quantification of Mycobacterium avium subspecies in porcine lymph nodes and liver.
    Acta Veterinaria Scandinavica 03/2013; 55(1):26. · 1.00 Impact Factor
  • Source

Full-text (2 Sources)

Available from
Jun 4, 2014