First molecular typing of Mycobacterium avium subspecies paratuberculosis identified in animal and human drinking water from dairy goat farms in Brazil

Abstract Mycobacterium avium subspecies paratuberculosis, the etiologic agent of Johne's disease or paratuberculosis, was identified by culture and/or polymerase chain reaction (PCR) in 50% and 30% of water samples for animal and human consumption, respectively, from ten dairy goat farms in Brazil. IS1311 restriction fragment length polymorphism analysis identified the isolates as cattle type C.

Molecular typing of Argentinian Mycobacterium avium subsp. paratuberculosis isolates by multiple-locus variable number-tandem repeat analysis

Multiple-locus variable number-tandem repeat analysis (MLVA) of Mycobacterium avium subspecies paratuberculosis (MAP) isolates may contribute to the knowledge of strain diversity in Argentina. Although the diversity of MAP has been previously investigated in Argentina using IS900-RFLP, a small number of isolates were employed, and a low discriminative power was reached. The aim of the present study was to test the genetic diversity among MAP isolates using an MLVA approach based on 8 repetitive loci. We studied 97 isolates from cattle, goat and sheep and could describe 7 different patterns: INMV1, INMV2, INMV11, INMV13, INMV16, INMV33 and one incomplete pattern. INMV1 and INMV2 were the most frequent patterns, grouping 76.3% of the isolates. We were also able to demonstrate the coexistence of genotypes in herds and co-infection at the organism level. This study shows that all the patterns described are common to those described in Europe, suggesting an epidemiological link between the continents.

Application of IS1311 locus 2 PCR-REA assay for the specific detection of ‘Bison type’ Mycobacterium avium subspecies paratuberculosis isolates of Indian origin.

Background & objectives: Of the three major genotypes of Mycobacterium avium subspecies paratuberculosis (MAP), ‘Bison type’ is most prevalent genotype in the domestic livestock species of the country, and has also been recovered from patients suffering from Crohn’s disease. Recently, a new assay based on IS1311 locus 2 PCR- restriction endonuclease analysis (REA) was designed to distinguish between ‘Indian Bison type’ and non-Indian genotypes. The present study investigated discriminatory potential of this new assay while screening of a panel of MAP isolates of diverse genotypes and from different geographical regions. Methods: A total of 53 mycobacterial isolates (41 MAP and 12 mycobacterium other than MAP), three MAP genomic DNA and 36 MAP positive faecal DNA samples from different livestock species (cattle, buffaloes, goat, sheep and bison) and geographical regions (India, Canada, USA, Spain and Portugal) were included in the study. The extracted DNA samples (n=92) were analyzed for the presence of MAP specific sequences (IS900, ISMav 2 and HspX) using PCR. DNA samples were further subjected to genotype differentiation using IS1311 PCR-REA and IS1311 L2 PCR-REA methods. Results: All the DNA samples (except DNA from non-MAP mycobacterial isolates) were positive for all the three MAP specific sequences based PCRs. IS1311 PCR-REA showed that MAP DNA samples of Indian origin belonged to ‘Bison type’. Whereas, of the total 19 non-Indian MAP DNA samples, 2, 15 and 2 were genotyped as ‘Bison type’, ‘Cattle type’ and ‘Sheep type’, respectively. IS1311 L2 PCR-REA method showed different restriction profiles of ‘Bison type’ genotype as compared to non-Indian DNA samples. Interpretation & conclusions: IS1311 L2 PCR-REA method successfully discriminated ‘Indian Bison type’ from other non-Indian genotypes and showed potential to be future epidemiological tool and for genotyping of MAP isolates.

First identification of Mycobacterium avium paratuberculosis sheep strain in Argentina

We here identified for the first time the presence of Mycobacterium avium paratuberculosis (MAP) sheep (S) strain in Argentina. IS900 polymerase chain reaction (PCR) was positive. The S strain was compared with MAP cattle (C) strains by using IS1311 PCR-restriction endonuclease analysis (PCR-REA), multiplex PCR and restriction fragment length polymorphism (RFLP) analysis.

Strain diversity within Mycobacterium avium subspecies paratuberculosis — A review.

Mycobacterium avium subspecies paratuberculosis (MAP), is the etiological agent of Johne’s disease (or paratuberculosis) in animals and has also been linked with Crohn’s disease of human beings. Extreme fastidious nature of the organism (MAP) has hampered studies on diversity within the organism. Studies based on phenotypic properties like growth rate, pigmentation, lipid profile etc., are unable to provide complete information on diversity of MAP organism in nature. However, with the advent of molecular assays (IS900 RFLP, PFGE, IS1311 PCR-REA, SSR typing, VNTR typing etc.) in last 2 decades, progress has been made to differentiate MAP strains. MAP isolates have been classified into various types and subtypes using these molecular tools. Optimization of these typing assays has led to generation of new information about MAP strains, subtypes, their comparative genomics, relative evolution, comparative virulence etc. Knowledge of strain diversity is important for better understanding of molecular and sero-epidemiology, infection and patho-biology, vaccine development and planning control strategies. The present review provides available information on MAP strains, host adaptations, their virulence, comparative genomics, relative genetic evolution and differentiation.