An IS900-like sequence found in a Mycobacterium sp. other than Mycobacterium avium subsp. paratuberculosis

Englund, Stina

doi:10.1016/s0378-1097(02)00552-9

Cited by 71 publications

(98 citation statements)

References 13 publications

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“…Almost all PCR protocols target the IS900 insertion sequence, which has been accepted as a standard marker for MAP. However, analysis of the genomes of other environmental Mycobacterium species has revealed sequences that are highly homologous to MAP IS900 (Englund et al, 2002). Therefore, other MAPspecific genetic elements have to be evaluated to improve the reliability of PCR detection of MAP.…”

Section: Pcrmentioning

confidence: 99%

Detection methods for Mycobacterium avium subsp paratuberculosis in milk and milk products: a review

Slaná¹,

Paolicchi²,

Janštová³

et al. 2008

Vet. Med. - Czech

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Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of paratuberculosis, a disease with considerable economic impact, principally on dairy cattle herds. Animals with paratuberculosis shed viable MAP especially in their milk, faeces and semen. MAP may have a role in the development of Crohn's disease in humans via the consumption of contaminated milk and milk products. The current methods of milk pasteurization are not sufficient to kill all MAP cells present in milk and MAP has been cultured from raw or pasteurized milk and isolated from cheese. The purpose of the present study was to review the different methods used for detection of MAP in milk and milk products. We analyze the current methods for direct or non direct identification of MAP and culture and molecular biology methods that can be applied to milk and milk products.

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Section: Pcrmentioning

confidence: 99%

Detection methods for Mycobacterium avium subsp paratuberculosis in milk and milk products: a review

Slaná¹,

Paolicchi²,

Janštová³

et al. 2008

Vet. Med. - Czech

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“…paratuberculosis by PCR, a few specific genetic sequences have previously been identified, such as the insertion sequence IS900 (21), the F57 element (41), and the hspX gene (15); but the value of these sequences for use in diagnostic assays for M. avium subsp. paratuberculosis infection remains unclear because of concerns about their specificity (13,16,42) or a lack of rigorous evaluations with large samples of clinical isolates. In fact, falsepositive PCR results have been reported for suspected paucibacillary M. avium subsp.…”

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confidence: 99%

Genomic Comparison of PE and PPE Genes in the Mycobacterium avium Complex

et al. 2009

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The Mycobacterium avium complex (MAC) comprises genomically similar but phenotypically divergent bacteria that inhabit diverse environments and that cause disease in different hosts. In this study, a wholegenome approach was used to examine the polymorphic PE (Pro-Glu) and PPE (Pro-Pro-Glu) gene families, implicated in immunostimulation and virulence. The four major groups of MAC organisms were examined, including the newly sequenced type strains of M. intracellulare and M. avium subsp. avium, plus M. avium subsp. paratuberculosis and M. avium subsp. hominissuis, for the purpose of finding genetic differences that could be exploited to design diagnostic tests specific to these groups and that could help explain their divergence in pathogenesis and host specificity. Unique and missing PPE genes were found in all MAC members except M. avium subsp. avium. Only M. intracellulare had a unique PE gene. Apart from this, most PE and PPE sequences were conserved, with average nucleotide sequence identities of 99.1 and 98.1%, respectively, among the M. avium subspecies, but only 82.9 and 79.7% identities with the PE and PPE sequences of M. intracellulare, respectively. A detailed analysis of the amino acid sequences was performed between M. avium subsp. paratuberculosis and M. avium subsp. hominissuis. Most differences were detected in the PPE proteins, with amino acid substitutions and frame shifts leading to unique amino acid sequences. In conclusion, several unique PPE proteins were identified in MAC organisms next to numerous polymorphisms in both the PE and PPE gene families. These substantial differences could help explain the divergence in phenotypes within the MAC and could lead to diagnostic tests with better discriminatory abilities.Mycobacterium avium and Mycobacterium intracellulare are collectively known as the Mycobacterium avium complex (MAC). For genotypic, phenotypic, and historical reasons, multiple subspecies of M. avium are recognized; these include Mycobacterium avium subsp. paratuberculosis, M. avium subsp. hominissuis, Mycobacterium avium subsp. avium, and M. avium subsp. silvaticum (50). All four M. avium subspecies and M. intracellulare possess a high degree of genetic similarity but are capable of infecting a diverse range of host species.M. avium subsp. paratuberculosis is the causative organism of Johne's disease (paratuberculosis), a debilitating chronic enteritis in ruminants (49), and has been implicated in Crohn's disease in humans (18). M. avium subsp. avium and M. avium subsp. silvaticum are limited almost exclusively to avian species (53), in which they cause tuberculosis. M. avium subsp. hominissuis is a recent designation and was added to reflect the distinction of human and porcine isolates from bird-type strains when genotypic methods showed that M. avium isolates from humans in particular but also pigs rarely shared the genetic profiles of organisms found in birds (38,53). M. avium subsp. hominissuis and M. intracellulare are ubiquitous, saprophytic mycobacteria commonly found in so...

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“…12 The specificity of the PCR test, including the IS900-based test on fecal samples, is generally considered to be very high, although there are a few reports of false-positive results. 6,4 Use of PCR on bacteria-free sample such as blood should be even more specific because unlike feces, blood should normally not contain bacteria that might share some homology with the MAP PCR target sequence. In fact, the cattle samples originated from a herd with a high incidence of clinical paratuberculosis, which provides a good degree of certainty that the animals were exposed to MAP.…”

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confidence: 99%

Comparison of Blood Polymerase Chain Reaction and Enzyme-Linked Immunosorbent Assay for Detection of Mycobacterium Avium Subsp. Paratuberculosis Infection in Cattle and Sheep

et al. 2005

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Abstract.A study was carried out to compare the performance of enzyme-linked immunosorbent assay (ELISA) and blood polymerase chain reaction (PCR) for diagnosis of paratuberculosis in cattle and sheep. For cattle, a set of 278 samples from 1 paratuberculosis-affected Friesian farm was used; it included 80 ELISApositive samples and 198 ELISA-negative samples from an age-matched group. Ninety-four samples were from heifers and 184 were from 2-5-year-old cows. The overall analysis showed a clear association (Fisher exact test [FET] P ϭ 0.0049) but a weak negative agreement (45.3%, kappa ϭ Ϫ0.1665 Ϯ 0.0994) between the 2 tests. It reflected a moderate agreement among heifers (87.7%, kappa ϭ 0.4471 Ϯ 0.2435) and a moderate disagreement among cows (62.7%, kappa ϭ Ϫ0.3670 Ϯ 0.1057). For sheep, 496 blood samples from 53 Latxa dairy flocks were used; 180 of the blood samples were from dam/offspring pairs. The overall association between the 2 tests on ovine samples was strong (FET, P ϭ 0.0005), whereas the agreement was low (kappa ϭ 0.1622 Ϯ 0.1188). There was slightly better agreement for ewes (kappa ϭ 0.2135 Ϯ 0.1992) than for lambs (kappa ϭ 0.1193 Ϯ 0.1301). There was also a highly unlikely proportion of dam/offspring positive results (FET, P Ͻ 0.0001, kappa ϭ 0.6269 Ϯ 0.1854). Four of 6 lambs that were necropsied 1 year after testing had paratuberculosis microscopic lesions in the ileocecal valve (3 lambs) or a PCR-positive result (4 lambs). These results suggest that blood PCR testing might be a potentially useful new approach in paratuberculosis diagnosis, especially in young animals.

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An IS900-like sequence found in a Mycobacterium sp. other than Mycobacterium avium subsp. paratuberculosis

Cited by 71 publications

References 13 publications

Detection methods for Mycobacterium avium subsp paratuberculosis in milk and milk products: a review

Detection methods for Mycobacterium avium subsp paratuberculosis in milk and milk products: a review

Genomic Comparison of PE and PPE Genes in the Mycobacterium avium Complex

Comparison of Blood Polymerase Chain Reaction and Enzyme-Linked Immunosorbent Assay for Detection of Mycobacterium Avium Subsp. Paratuberculosis Infection in Cattle and Sheep

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