ABSTRACT
According to general consensus, the global climate is changing, which may also affect agricultural and livestock production. The potential impact of climate change on food security is a widely debated and investigated issue. Nonetheless, the specific impact on safety of food and feed for consumers has remained a less studied topic. This review therefore identifies the various food safety issues that are likely to be affected by changes in climate, particularly in Europe. Amongst the issues identified are mycotoxins formed on plant products in the field or during storage; residues of pesticides in plant products affected by changes in pest pressure; trace elements and/or heavy metals in plant products depending on changes in their abundance and availability in soils; polycyclic aromatic hydrocarbons in foods following changes in long-range atmospheric transport and deposition into the environment; marine biotoxins in seafood following production of phycotoxins by harmful algal blooms; and the presence of pathogenic bacteria in foods following more frequent extreme weather conditions, such as flooding and heat waves. Research topics that are amenable to further research are highlighted.
Subject(s)
Consumer Product Safety , Food Contamination/analysis , Food Supply , Greenhouse Effect , Environmental Health , Europe , Food Microbiology , HumansABSTRACT
This review describes horizontal gene transfer from a historical point of view, with descriptions of the first instances of the different bacterial transfer mechanisms: conjugation, transduction and transformation, as well as examples of some of the early acknowledged transfer events. Gene transfer from four selected foodborne pathogens: Escherichia coli, Listeria monocytogenes,Staphylococcus aureus and Salmonella are highlighted.
Subject(s)
Bacteria/genetics , Food Microbiology , Gene Transfer, Horizontal , Virulence Factors/genetics , Animals , Bacteria/pathogenicity , Conjugation, Genetic/genetics , Escherichia coli/genetics , Escherichia coli/pathogenicity , Food Supply , Listeria monocytogenes/genetics , Listeria monocytogenes/pathogenicity , Mice , Salmonella/genetics , Salmonella/pathogenicity , Staphylococcus aureus/genetics , Staphylococcus aureus/pathogenicity , Transduction, Genetic , Transformation, Bacterial/geneticsABSTRACT
Bacteria use various ways to transfer genetic information. These methods include: conjugation, which requires cell to cell contact between cells, transduction, which is bacteriophage-facilitated transfer of genetic information, and transformation, which is the uptake of free DNA from the environment. Usually the genes to be transferred lie on mobile genetic elements, pieces of DNA that encode proteins important to facilitate movement of DNA within or between genomes. This review highlights the transfer methods and the role of the assorted mobile genetic elements in the evolution of four foodborne bacterial pathogens: Escherichia coli O157:H7, Salmonella, Staphylococcus aureus and Listeria monocytogenes.
Subject(s)
Bacteria/genetics , Bacterial Infections/genetics , Bacterial Infections/transmission , Gene Transfer, Horizontal , Host-Pathogen Interactions/physiology , Bacteria/pathogenicity , Escherichia coli O157/genetics , Escherichia coli O157/pathogenicity , Evolution, Molecular , Food Microbiology , Listeria monocytogenes/genetics , Listeria monocytogenes/pathogenicity , Salmonella/genetics , Salmonella/pathogenicity , Staphylococcus aureus/genetics , Staphylococcus aureus/pathogenicityABSTRACT
Genes encoding virulence determinants are transferred between species in many different environments. In this review we describe gene transfer events to and from different species of bacteria, from bacteria to plants, and from plants to bacteria. Examples of the setting for these transfer events include: the GI tract, the rumen, the oral cavity, and in food matrixes. As a case study, the flux of virulence factors from E.coli O157:H7 is described as an example of gene flow in the environment.
