Publications by authors named "L Joens"

In vitro passage of Campylobacter jejuni strains results in phenotypic changes and a general loss of virulence, as is the case with the genome-sequenced strain C. jejuni NCTC11168. Re-sequencing of a virulent strain of NCTC11168 identified 41 SNPs or indels involving 20 genes, four intergenic regions and three pseudogenes.

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In this work, we investigated the Campylobacter jejuni dps (DNA binding protein from starved cells) gene for a role in biofilm formation and cecal colonization in poultry. In vitro biofilm formation assays were conducted with stationary-phase cells in cell culture plates under microaerophilic conditions. These studies demonstrated a significant (>50%) reduction in biofilm formation by the C.

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The consumption of raw oysters is an important risk factor in the acquisition of food-borne disease, with Salmonella being one of a number of pathogens that have been found in market oysters. Previous work by our lab found that Salmonella was capable of surviving in oysters for over 2 months under laboratory conditions, and this study sought to further investigate Salmonella's tissue affinity and mechanism of persistence within the oysters. Immunohistochemistry was used to show that Salmonella was capable of breaching the epithelial barriers, infecting the deeper connective tissues of the oysters, and evading destruction by the oysters' phagocytic hemocytes.

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Iron acquisition is an absolute requirement by most microorganisms for host survival. In this work, we investigated the Campylobacter jejuni iron binding Dps protein for a potential role in virulence. In vitro assays using J774A.

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To determine if Salmonella-contaminated oysters are reaching consumer tables, a survey of raw oysters served in eight Tucson restaurants was performed from October 2007 to September 2008. Salmonella spp. were isolated during 7 of the 8 months surveyed and were present in 1.

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