Publications by authors named "Maria E Scott"

The Food Safety and Inspection Service (FSIS) conducts microbiological baseline studies to determine national prevalence of select foodborne pathogens in federally inspected meat and poultry products and to obtain data for risk assessments. The FSIS conducted a baseline study from 1 June 2017 through 31 May 2018 to characterize and determine the prevalence of Salmonella and assess the occurrence of Shiga toxin-producing Escherichia coli (STEC) in a variety of raw pork products. In total, 4,014 samples from slaughter and processing establishments were analyzed for Salmonella; a subset of these samples (1,395) from slaughter establishments were also analyzed for STEC.

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We show here that silver nanoparticles (AgNP) were intrinsically antibacterial, whereas gold nanoparticles (AuNP) were antimicrobial only when ampicillin was bound to their surfaces. Both AuNP and AgNP functionalized with ampicillin were effective broad-spectrum bactericides against Gram-negative and Gram-positive bacteria. Most importantly, when AuNP and AgNP were functionalized with ampicillin they became potent bactericidal agents with unique properties that subverted antibiotic resistance mechanisms of multiple-drug-resistant bacteria.

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Shiga toxin-producing Escherichia coli (STEC) are a significant cause of zoonotic foodborne diarrheal disease in industrialized nations. In addition to Shiga toxin most STEC produce the enterohemolysin (EhxA) toxin. The EhxA toxin is encoded by the ehxCABD operon located on the large plasmid carried by STEC, yet its role in pathogenesis is unknown.

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The type II secretion (T2S) system is present in many gram-negative species, both pathogenic and nonpathogenic, where it supports the delivery of a variety of toxins, proteases, and lipases into the extracellular environment. In Vibrio cholerae, the T2S apparatus is composed of 12 Eps proteins that assemble into a multiprotein complex that spans the entire cell envelope. Two of these proteins, EpsM and EpsL, are key components of the secretion machinery present in the inner membrane.

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Shiga toxin-producing Escherichia coli (STEC) 091:H21 strain B2F1, an isolate from a patient with the hemolytic uremic syndrome (HUS), produces elastase-activatable Shiga toxin (Stx) type 2d and adheres well to human colonic epithelial T84 cells. This adherence phenotype occurs even though B2F1 does not contain the locus of enterocyte effacement (LEE) that encodes the primary adhesin for E. coli O157:H7.

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