Mycobacterium avium subsp. paratuberculosis: an Unconventional Pathogen?

Srinand Sreevatsan; Natalia Cernicchiaro; Radhey Kaushik

doi:10.1128/9781555815479.ch17

Chapter 17 : Mycobacterium avium subsp. paratuberculosis: an Unconventional Pathogen?

Authors: Srinand Sreevatsan¹, Natalia Cernicchiaro², Radhey Kaushik³

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Affiliations: 1: Department of Veterinary Population Medicine and Department of Veterinary Biomedical Sciences, University of Minnesota, St. Paul, MN 55108; 2: Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN 55108; 3: Department of Biology and Microbiology and Department of Veterinary Sciences, NPB Rm. 252A, Box 2140D, South Dakota State University, Brookings, SD 57007

Content Type: Monograph

Publication Year: 2009

Category: Food Microbiology; Applied and Industrial Microbiology

Book DOI: 10.1128/9781555815479

Chapter DOI: 10.1128/9781555815479.ch17

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Abstract:

The Mycobacterium avium complex includes the closely related Mycobacterium avium subsp. avium, Mycobacterium avium subsp. paratuberculosis, and Mycobacterium intracellulare, as well as the wood pigeon bacillus. In recent years, M. avium complex strains have assumed greater importance in human medicine, largely because of intractable Mycobacterium avium complex infections in AIDS patients and also because of the possible association of M. avium subsp. paratuberculosis with Crohn’s disease. M. avium subsp. paratuberculosis is the causative agent of Johne’s disease (or paratuberculosis), a debilitating chronic enteritis in ruminants. Current research based on understanding of the genomic diversity among M. avium subsp. paratuberculosis strains is now enabling elucidation of mechanisms of survival in the environment, host specificity, and the association of specific genotypes with overt disease versus subclinical states. The infected macrophages play a critical role in the pathogenesis of the disease and dictate the disease outcome. In this chapter the authors have investigated the nature of macrophage M. avium subsp. paratuberculosis interactions. Contaminated domestic water, pasteurized milk, contaminated meat or other food, environmental sources, and direct animal exposures have all been suggested as possible mechanisms of human exposure to M. avium subsp. paratuberculosis. Comprehensive analysis of these survival mechanisms at the transcriptome and proteome levels is expected to improve one's understanding of host-pathogen and pathogen-environment interactions of M. avium subsp. paratuberculosis.

Citation: Sreevatsan S, Cernicchiaro N, Kaushik R. 2009. Mycobacterium avium subsp. paratuberculosis: an Unconventional Pathogen?, p 311-321. In Jaykus L, Wang H, Schlesinger L (ed), Food-Borne Microbes. ASM Press, Washington, DC. doi: 10.1128/9781555815479.ch17

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