Research Publications (Food Safety)

Microbiology Resource Announcements, Ahead of Print. Campylobacter jejuni is the leading pathogen that causes foodborne infections. Here, we report the complete genome sequences of four C. jejuni strains isolated from retail chicken meat and broiler feces samples. Genes encoding type VI secretion and antibiotic resistance were detected among these isolates.

Environmental Microbiology, Accepted Article. The Splendidus clade is the largest clade in Vibrionaceae, and its members are often related to mortality of marine animals with huge economic losses. The molecular bases of their pathogenicity and virulence, however, remain largely unknown.

by Ilia Gelfat, Yousuf Aqeel, Jacqueline M. Tremblay, Justyna J. Jaskiewicz, Anishma Shrestha, James N. Lee, Shenglan Hu, Xi Qian, Loranne Magoun, Abhineet Sheoran, Daniela Bedenice, Colter Giem, Avinash Manjula-Basavanna, Amanda R. Pulsifer, Hann X. Tu, Xiaoli Li, Marilyn L. Minus, Marcia S. Osburne, Saul Tzipori, Charles B. Shoemaker, John M. Leong, Neel S.

Salmonella is a leading cause of foodborne illness worldwide and is a common concern in food safety. Salmonella enterica displaying resistance to extended-spectrum cephalosporins (ESCs) and fluoroquinolone (FQs) has been deemed a high-priority pathogen by the World Health Organization. Co-resistance to ESCs and FQs has been reported in S. enterica serovar Thompson (S. Thompson). However, the genetic context of ESCs and FQs resistance genes in S. Thompson lacks sufficient characterization.

Jerusalem artichoke (JA) is a fructan-accumulating crop that has gained popularity in recent years. The objective of the present study was to determine the dynamics of the JA-microbiome during storage. The microbial population on the surface of the JA tuber was determined by next-generation sequencing of 16S rRNA amplicons. Subsequently, the changes in carbohydrate and degree of polymerization of fructan in tubers during storage were measured.

mBio, Ahead of Print. The role of the gut microbiota in the pathogenesis of Shigella flexneri remains largely unknown. To understand the impact of the gut microbiota on S. flexneri virulence, we examined the effect of interspecies interactions with Bacteroides thetaiotaomicron, a prominent member of the gut microbiota, on S. flexneri invasion. When grown in B. thetaiotaomicron-conditioned medium, S.

mBio, Ahead of Print. The ubiquitous presence of toxic arsenate (AsV) in the environment has raised mechanisms of resistance in all living organisms. Generally, bacterial detoxification of AsV relies on its reduction to arsenite (AsIII) by ArsC, followed by the export of AsIII by ArsB. However, how pathogenic species resist this metalloid remains largely unknown.

Infection and Immunity, Ahead of Print. Listeria monocytogenes is a Gram-positive facultative anaerobe and an excellent model pathogen for investigating regulatory changes that occur during infection of a mammalian host. SpxA1 is a widely conserved transcriptional regulator that induces expression of peroxide-detoxifying genes in L. monocytogenes and is thus required for aerobic growth. SpxA1 is also required for L.

The ecology of Listeria monocytogenes and Pseudomonas spp. during the slaughtering of spotted sorubim ( Pseudoplatystoma corruscans ) in a fish processing facility was assessed. Fish samples (n = 28) were obtained in different points of slaughtering (A: arrival, B: washing, C: gutting, and D: cooling) and subjected to detection of L. monocytogenes and enumeration of Pseudomonas spp. High frequencies of Listeria spp. (17/28 to 22/28) and L.

Similar to Pu-erh tea, Liupao tea is a post-fermented tea that is produced through natural fermentation by microorganisms. Penicillium citrinum has been detected is involved in multiple production processes of Liupao tea that can produce citrinin, a secondary metabolite with renal toxicity; however, the effect of P. citrinum on the quality of Liupao tea has not been investigated yet.

The primary seafood-borne pathogen Vibrio parahaemolyticus seriously threats the health of consumers preferring raw-fish products, becoming a global concern in food safety. In the present study, we found ferrous sulfate (FeSO4), a nutritional iron supplement, could efficiently induce the death of V. parahaemolyticus. Further, the bactericidal mechanisms of FeSO4 were explored.

Nonspecific binding of proteins from complex food matrices is a significant challenge associated with a biosensor using gold nanoparticles (AuNPs). To overcome this, we developed an efficient EDTA chelating treatment to denature milk proteins and prevent their adsorption on AuNPs. The use of EDTA to solubilize proteins enabled a sensitive label-free apta-sensor platform for colorimetric detection of Staphylococcus aureus in milk and infant formula.

Bioenzymatic degradation of aflatoxin B1 (AFB1) is a safe, efficient and environmentally friendly detoxification technology.

Willows (Salix spp.) are promising extractors of cadmium (Cd), with fast growth, high biomass production, and high Cd accumulation capacity. However, the molecular mechanisms underlying Cd uptake and detoxification are currently poorly understood.

Storage at the putative chilling threshold temperature (CTT) to avoid chilling injury still limits postharvest handling of tropical fruit like banana in that ripening may occur at the CTT. To determine whether chilling injury (CI) symptoms would develop in mature green (MG) banana fruit if the CTT exposure was extended by inhibiting ethylene action and thus ripening, 1-methylcyclopropene (1-MCP) was applied.

Background

Corynebacterium accolens (C. accolens) is a common nasal colonizer, whereas Staphylococcus aureus (S. aureus) is typically regarded a pathogenic organism in patients with chronic rhinosinusitis (CRS). This study aims to evaluate the interaction of the two bacteria in vitro.

Methods

The type VI secretion system (T6SS) is widely distributed in diverse bacterial species and habitats where it is required for interbacterial competition and interactions with eukaryotic cells. Previous work described the role of a T6SS in the beneficial symbiont, Vibrio fischeri, during colonization of the light organ of Euprymna scolopes squid. However, the prevalence and diversity of T6SSs found within the distinct symbiotic structures of this model host have not yet been determined.

Aflatoxin B1 (AFB1) contaminates rice during harvest or storage and causes a considerable risk to human and animal health. In this study, Trametes versicolor AFB1–degrading enzyme (TV–AFB1D) gene recombinantly expressed in engineered E. coli BL21 (DE3) and Saccharomyces cerevisiae. The TV–AFB1D enzymatic characteristics and AFB1 degradation efficiency in contaminated rice were investigated. Results showed that the size of recombinant TV-AFB1D expressing in E. coli BL21 (DE3) and S.

Bacillus cereus sensu lato (B. cereus sl) is important spoilage bacteria causing milk structure and flavor changes and is ubiquitous in the environment. This study addresses the biodiversity, toxicity, and proteolytic activity of B. cereus sl from 82 environmental samples and 18 raw bovine milk samples from a dairy farm in the region of Tianjin. In sum, 47 B. cereus sl isolates were characterized through biochemical tests, 16S rRNA gene sequencing, and panC gene analysis.

Synthetic pesticides are extensively and injudiciously applied to control agriculture and household pests worldwide. Due to their high use, their toxic residues have enormously increased in the agroecosystem in the past several years. They have caused many severe threats to non-target organisms, including humans. Therefore, the complete removal of toxic compounds is gaining wide attention to protect the ecosystem and the diversity of living organisms.

Crater Lake, Oregon is an oligotrophic freshwater caldera lake fed by thermally and chemically enriched hydrothermal springs. These vents distinguish Crater Lake from other freshwater systems and provide a unique ecosystem for study. This study examines the community structure of benthic microbial mats occurring with Crater Lake hydrothermal springs. Small subunit rRNA gene amplicon sequencing from eight bacterial mats was used to assess community structure.

Probiotic attributes of lactic acid bacteria isolated from goat and sheep milk samples were analysed by culturing them on an MRS agar medium. The most potential isolates, GMB24 and SMB16, were identified by biochemical tests which had ability to tolerate different concentrations of acid and bile and phenol resistance. They were further identified as Enterococcus faecium GMB24 and Enterococcus hirae SMB16 by 16S rRNA gene sequencing approach.

This study aimed to evaluate and model the antimicrobial action of different concentrations of Croton blanchetianus essential oil (CBEO) on the behavior of six bacterial species in vitro. CBEO extraction was performed by hydrodistillation and characterized by CG-MS.

Intestinal peristalsis is essential for gastrointestinal function, which could maintain the appropriate progression and digestion of food and reduce bacterial aggregation through mixing function. Even though certain ingredients of foodstuff are known to increase or decrease intestinal peristalsis, the role of environmental pollutants on intestinal peristalsis is relatively unknown.

Mycotoxins are bioaccumulative contaminants impacting animals and humans. The simultaneous detection of frequent active exposures and accumulated mycotoxin level (s) in exposed organisms would be the most ideal to enable appropriate actions. However, few methods are available for the purpose, and there is a demand for dedicated, sensitive, reliable, and practical assays.