Genomic Polymorphisms for Mycobacterium avium subsp. paratuberculosis Diagnostics

摘要: Mycobacterium avium subsp. paratuberculosis is a serious pathogen of domestic ruminants, in which it causes (Johne's disease), chronic and eventually fatal inflammatory bowel disease. Its rising incidence many regions the world has resulted significant economic losses to livestock industry (13). This organism also infects free-ranging wildlife species (16). The impact M. nonruminant largely unknown; however, potential for interspecies transmission important implications control programs. being actively investigated as possible cause debilitating human disease, Crohn's disease (4, 5, 18). Effective Johne's investigation link have been hampered by lack effective assays easily accurately diagnose infections. Commercially available serological bovine are convenient but offer poor sensitivity, especially during subclinical Moreover, owing high degree genetic similarity between other members complex, proteins that recognized early stages infection not specific (14). Since highly prevalent environment associated with similar clinical syndrome mammals, capacity differentiate these closely related organisms essential rational epidemiologic assessment. Previous work identified number sequences absent from mycobacteria, such insertion sequence IS900 (11), F57 element (21), hspX gene (9), value diagnostics remains unclear. Although PCR testing multicopy widely used, there concerns about its specificity validity direct proxy paratuberculosis. IS900-like elements found unrelated (10), complex elements, including IS1311 (7) IS1626 (22), share considerable similarity. In cases hspX, their date rigorously evaluated large sample isolates. More recently, data derived genome sequencing projects suggested polymorphic genomic may serve diagnosis Our microarray-based comparisons using strain 104 reference revealed 14 polymorphisms (LSPs) variably present among small collection isolates. Three appeared be (LSPAs) isolates (23). Conversely, computational K10 (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"NC_002944","term_id":"41406098","term_text":"NC_002944"}}NC_002944) (http://www.tigr.org) DNA former missing or divergent latter (2, 3, 19). We 17 varying length 2.9 66 kb unique K10; we call LSPPs. Such can expected lend themselves nucleic acid-based diagnostic tests and, if they encode immunogenic proteins, immunological well. One these, 19-kb LSPP12, previously documented (8, 23). Another, 98-kb segment encompasses LSPP14 LSPP15, includes within 38-kb was recently described an paratuberculosis-specific putative pathogenicity island (24). The objective our study assess LSPs To diagnostically paratuberculosis, LSPP must only should non-M. LSPA molecular consistently broad therefore tested distribution LSPPs 3 LSPAs across panel 383 results indicate LSP regions, although distinct prototype sequences, heterogeneously distributed geographically diverse so required diagnostics. However, subset do appear prove useful development evaluation hypothesis.