Research Publications (Food Safety)

Applied and Environmental Microbiology, Ahead of Print. Vibrio cholerae is a ubiquitously distributed human pathogen that naturally inhabits marine and estuarine ecosystems. Two serogroups are responsible for causing cholera epidemics, O1 and O139, but several non-O1 and non-O139 V. cholerae (NOVC) strains can induce cholera-like infections. Outbreaks of V.

Applied and Environmental Microbiology, Ahead of Print. Temperature is a critical environmental factor that affects the cell growth of dinoflagellates and bloom formation. To date, the molecular mechanisms underlying the physiological responses to temperature variations are poorly understood.

Applied and Environmental Microbiology, Ahead of Print. The high host specificity of phages is a real challenge in the therapy applications of the individual phages. This study aimed to edit the long tail fiber proteins (pb1) of a T5-like phage to obtain the engineered phages with expanded plaquing host range.

Applied and Environmental Microbiology, Ahead of Print. We investigated the influence of hapR sequence mutations on the biofilm formation of Vibrio cholerae. In this study, hapR sequences from 85 V. cholerae strains belonging to both pandemic and nonpandemic serogroup were investigated through phylogenetic and sequence analyses. Biofilm formation assays under aerobic and anaerobic conditions were also performed.

Applied and Environmental Microbiology, Ahead of Print. Broiler chickens are an important source of Campylobacter to humans and become colonized on the farm, but the role of the litter in the ecology of Campylobacter is still not clear. The aim of this study was to examine the relationship between Campylobacter and the changes in the litter microbiome throughout the broiler production cycle.

Applied and Environmental Microbiology, Ahead of Print. When processing low-moisture, high-fat foods such as peanut butter and nuts, water-based sanitization is unsuitable due to the immiscible nature of water and fats. Dry sanitization mainly uses flammable compounds such as isopropanol, requiring equipment cooling before application.

Applied and Environmental Microbiology, Ahead of Print. The genus Vibrio is characterized by high metabolic flexibility and genome plasticity and is widely distributed in the ocean from euphotic layers to deep-sea environments.

Applied and Environmental Microbiology, Ahead of Print. Microbe-mediated transformations of arsenic (As) often require As to be taken up into cells prior to enzymatic reaction. Despite the importance of these microbial reactions for As speciation and toxicity, understanding of how As bioavailability and uptake are regulated by aspects of extracellular water chemistry, notably dissolved organic matter (DOM), remains limited.

Applied and Environmental Microbiology, Ahead of Print. Lactose utilization is one of the general biochemical characteristics of Escherichia coli, and the lac operon is responsible for this phenotype, which can be detected on lactose-containing media, such as MacConkey agar, after 24 h of incubation. However, some Shiga toxin-producing E.

Applied and Environmental Microbiology, Ahead of Print. Shigella invasion plasmid antigen B (IpaB) plays an important role in causing shigellosis. While IpaB’s protein structure, contribution to disease mechanism, and protective immunity against Shigella infection have been well studied, the significance of individual antigenic domains, especially at the N terminus, has not been systematically characterized.

Applied and Environmental Microbiology, Ahead of Print. Lignin is an aromatic plant cell wall polymer that facilitates water transport through the vasculature of plants and is generated in large quantities as an inexpensive by-product of pulp and paper manufacturing and biorefineries. Although lignin’s ability to reduce bacterial growth has been reported previously, its hydrophobicity complicates the ability to examine its biological effects on living cells in aqueous growth media.

Applied and Environmental Microbiology, Ahead of Print. Whole-genome sequencing (WGS) for public health surveillance and epidemiological investigation of foodborne pathogens predominantly relies on sequencing platforms that generate short reads.

Applied and Environmental Microbiology, Ahead of Print. Vibrio spp. and phytoplankton are naturally abundant in marine environments. Recent studies have suggested that the co-occurrence of phytoplankton and the pathogenic bacterium Vibrio parahaemolyticus is due to shared ecological factors, such as nutrient requirements.

Applied and Environmental Microbiology, Ahead of Print. Bacillus cereus sensu lato (s.l.) includes foodborne pathogens, as well as beneficial microorganisms, such as bioinsecticides. Some of the beneficial and commercially used B. cereus s.l. strains have been shown to carry enterotoxin genes, the products of which can cause toxicoinfection in humans.

Applied and Environmental Microbiology, Ahead of Print. Bacterial species in the polymicrobial community evolve interspecific interaction relationships to adapt to the survival stresses imposed by neighbors or environmental cues. Pseudomonas aeruginosa and Staphylococcus aureus are two common bacterial pathogens frequently coisolated from patients with burns and respiratory disease.

Applied and Environmental Microbiology, Ahead of Print. The growth of sulfate-reducing bacteria (SRB) and associated hydrogen sulfide production can be problematic in a range of industries such that inhibition strategies are needed. A range of SRB can reduce metal ions, a strategy that has been utilized for bioremediation, metal recovery, and synthesis of precious metal catalysts.

Applied and Environmental Microbiology, Ahead of Print. The alternative sigma factor B (σB) contributes to the stress tolerance of the foodborne pathogen Listeria monocytogenes by upregulating the general stress response. We previously showed that σB loss-of-function mutations arise frequently in strains of L. monocytogenes and suggested that mild stresses might favor the selection of such mutations.

Applied and Environmental Microbiology, Ahead of Print. Blooms of many dinoflagellates, including several harmful algal bloom (HAB) species, are seeded and revived through the germination of benthic resting cysts. Temperature is a key determinant of cysts’ germination rate, and temperature–germination rate relationships are therefore fundamental to understanding species’ germling cell production, cyst bed persistence, and resilience to climate warming.

Applied and Environmental Microbiology, Ahead of Print. Bacteria coping with oxygen deficiency use alternative terminal electron acceptors for NADH regeneration, particularly fumarate. Fumarate is reduced by the FAD_binding_2 domain of cytoplasmic fumarate reductase in many bacteria. The variability of the primary structure of this domain in homologous proteins suggests the existence of reducing activities with different specificities.

Applied and Environmental Microbiology, Ahead of Print. Selection for Listeria monocytogenes strains that are tolerant to quaternary ammonium compounds (such as benzalkonium chloride [BC]) is a concern across the food industry, including in fresh produce processing environments. This study evaluated the ability of 67 strains of produce-associated L. monocytogenes and other Listeria spp.

Applied and Environmental Microbiology, Volume 88, Issue 10, May 2022. The infection of a bacterium by a tailed phage starts from the adsorption process, which consists of a specific and strong interaction between viral proteins called receptor binding proteins (RBPs) and receptors located on the bacterial surface.

Applied and Environmental Microbiology, Volume 88, Issue 10, May 2022. As the cases of Salmonella enterica infections associated with contaminated water are increasing, this study was conducted to address the role of surface water as a reservoir of S. enterica serotypes.

Applied and Environmental Microbiology, Volume 88, Issue 10, May 2022. To maintain food safety and flock health in broiler chicken production, biosecurity approaches to keep chicken barns free of pathogens are important. Canadian broiler chicken producers must deep clean their barns with chemical disinfectants at least once annually (full disinfection [FD]) and may wash with water (water wash [WW]) throughout the year.

Applied and Environmental Microbiology, Volume 88, Issue 10, May 2022. To understand the molecular mechanisms that contribute to the stress responses of the important foodborne pathogen Listeria monocytogenes, we collected 139 strains (meat, n = 25; dairy, n = 10; vegetable, n = 8; seafood, n = 14; mixed food, n = 4; and food processing environments, n = 78), mostly isolated in Ireland, and subjected

Applied and Environmental Microbiology, Volume 88, Issue 10, May 2022. The Gram-positive bacterium Listeria monocytogenes is an important pathogen that causes a foodborne illness with a high percentage of fatalities. Surface proteins, specifically expressed from a wide range of L. monocytogenes serotypes under selective enrichment culture conditions, can serve as targets for the detection and isolation of this pathogen using antibody-based methods.