This Article Full Text (PDF) Other Versions of this Article: AEM.02740-07v1 74/6/1757    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Heithoff, D. M. Articles by Mahan, M. J. Search for Related Content PubMed PubMed Citation Articles by Heithoff, D. M. Articles by Mahan, M. J. Agricola Articles by Heithoff, D. M. Articles by Mahan, M. J.

 Previous Article  |  Next Article 

Appl. Environ. Microbiol. doi:10.1128/AEM.02740-07
Copyright (c) 2008, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.

Human Salmonella Clinical Isolates That Are Distinct From Those of Animal Origin

Dept. of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106, USA; Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84132; School of Veterinary Medicine, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616; University of Sydney, Faculty of Veterinary Science, Camden NSW 2570

^* To whom correspondence should be addressed. Email: mahan{at}lifesci.lscf.ucsb.edu.

	Abstract

The global trend towards intensive livestock production has led to significant public health risks and industry-associated losses due to an increased incidence of disease and contamination of livestock-derived food products. A potential contributing factor to these health concerns is the prospect that selective pressure within a particular host may give rise to bacterial strain variants that exhibit enhanced fitness in the current host relative to the parental host from which the strain was derived. Here we assessed 184 Salmonella enterica human and animal clinical isolates for their virulence capacity in mice, and for the presence of the Salmonella virulence plasmid, encoding the SpvB actin cytotoxin required for systemic survival, and Pef fimbriae implicated in adherence to murine intestinal epithelium. All (21/21) Typhimurium clinical isolates derived from animals were virulent in mice, whereas many (16/41) Typhimurium isolates derived from human salmonellosis patients lacked this capacity. Additionally, many (10/29) Typhimurium isolates derived from gastroenteritis patients did not possess the Salmonella virulence plasmid, contrary to all animal or human bacteremia isolates tested. Last, among Typhimurium isolates that harbored the Salmonella virulence plasmid, 6 of 31 derived from human salmonellosis patients were avirulent in mice, which is in contrast to the virulent phenotype exhibited by all animal isolates examined. These studies suggest that Salmonella isolates derived from human salmonellosis patients are distinct from those of animal origin. Characterization of these bacterial strain variants may provide insight into their relative pathogenicity as well as to the development of treatment and prophylactic strategies for salmonellosis.

This article has been cited by other articles:

• Heithoff, D. M., Enioutina, E. Y., Bareyan, D., Daynes, R. A., Mahan, M. J. (2008). Conditions That Diminish Myeloid-Derived Suppressor Cell Activities Stimulate Cross-Protective Immunity. Infect. Immun. 76: 5191-5199 [Abstract] [Full Text]