Some enterococci of food origin produce bacteriocins that exert anti-Listeria activity. Enterococci are used as probiotics to improve the microbial balance of the. Enterococci can cause food intoxication through production of biogenic amines and can be a reservoir for .. Enterococci at the crossroads of food safety. C. M. A. P. Franz, W. H. Holzapfel and M. E. Stiles, “Enterococci at the Crossroads of Food Safety” International Journal of Food Microbiology, Vol. 47, No.
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There is evidence that enterococci could find potential application in the processing of some fermented dairy crossrroads [ 175 ]. The finding of non human VRE suggests the presence of community eenterococci animal reservoirs for these bacteria, where they have been selected through the use of avoparcin as a feed additive. Phenotypic characteristics of Enterococcus faecium variants saafety by intergenic ribosomal polymerase chain reaction and E.
Virulence of enterococci is strongly enhanced by their frequent resistance to commonly used antibiotics. Antibiotic-resistant enterococci can be provided to the human gut by contaminated foods especially of animal origin and environment, including people and animals. Enterococci are not only intrinsically resistant to several antibiotics, but are also characterised by a potent and unique ability to exchange genetic material. To the contrary, many sfety suggest that certain strains of enterococci in some cheeses may be highly desirable on the basis of enerococci positive contribution to flavour development during the cheese ripening.
Clearly, there is no consensus on the acceptance of their presence in foodstuffs and their role as primary pathogens is still a question mark.
Therefore, although a connection between the occurrence of VRE in meat and nosocomial infections has not yet been clearly proved, epidemiological data would suggest that both clonal dissemination through the food chain and horizontal gene transfer between a variety of different strains are involved in the VRE spreading outside the hospital. Enterococci constitute a large proportion of the autochthonous bacteria associated with the mammalian gastrointestinal tract.
Enterococci at the crossroads of food safety? 
Indeed, enterococci commonly occur in large numbers in vegetables, plant material and foods, especially enerococci of animal origin such as fermented sausages and cheeses. These findings suggest that a possible link between the use of avoparcin and other antibiotics used in livestock, the selection of VRE or AREand humans becoming colonised via the food chain exists. The use of this class of antimicrobials is of utmost importance in clinical therapy against multiple antibiotic-resistant strains or in the case of allergy to other antibiotics, e.
Modern classification techniques resulted in the transfer of some members of the genus Streptococcus, notably some of the Lancefield’s group D streptococci, to the new genus Enterococcus.
Enterococci at the crossroads of food safety?
Several reports carried out in European countries and the USA in recent years indicate that colonisation with VRE frequently occurs in the community, and that many animal, food and environmental reservoirs can act as community sources for VRE outside the health care setting. However, this measure should be complemented by a more prudent use of antibiotics in human medicine.
Once rejected from the environment by means of human faeces or animal ejecta, they are able to colonise diverse niches because of their exceptional aptitude to resist or grow in hostile environments. Fokd of resistance to antibiotics.
Food-borne enterococci integrate into oral biofilm: Continuing high prevalence of vanA-type vancomycin-resistant enterococci on Norvegian poultry farms three years after avoparcin was banned. Enterococci can be used as indicators of faecal contamination.
Close mobile search navigation Article navigation. The extremely high level of antibiotic resistance observed in enterococci and their widespread finding in raw foods are two key elements contributing to the frequent recovery of antibiotic-resistant enterococci ARE in both unfermented and fermented foods.
A recent epidemiological study carried out in France, which showed common pulsed field gel electrophoresis PFGE patterns in antibiotic-resistant E.
In addition, the notable resistance of enterococci to adverse environmental conditions explains their ability to colonise different ecological niches and their spreading within the food chain through contaminated animals and foods. Trans-conjugation in which starter strains acquired virulence determinants from medical strains was also demonstrated . Often, the same plasmid may encode a sex pheromone response and either antibiotic resistance or haemolysin production genes [ 122627 ].
Therefore, the barrier separating enterococci as inoffensive contaminants from pathogens appears most fragile. Clearly, the presence of enterococci is ineluctable also in many dairy products.
With the emergence of glycopeptide resistance in enterococci especially E. Characterization of lactic acid bacteria isolated from artisanal Travnik young cheeses, sweet creams and sweet kajmaks over four seasons. The presence of enterococci in dairy products has long been considered an indication of insufficient sanitary conditions during the production and fo of milk. Enterococci from foods Giorgio Giraffa. Concerning gene transfer route of transmission, recent molecular studies on sequence polymorphism of Tnencoding vancomycin resistance, within VRE from humans, pigs and poultry suggest that the primary transmission is from animals to humans and not the other way around .
Enterococci from foods | FEMS Microbiology Reviews | Oxford Academic
The sarety with the taxonomy of enterococci is generally that they are a heterogeneous group of Gram-positive cocci sharing many characteristics with the genera Streptococcus and Lactococcus. It was therefore suggested that a proper heat treatment during processing, such as in the fo of cooked, unfermented meats, would be necessary to eliminate enterococci as spoilage microflora in fermented meats . A wide variety of fermented meat products is produced in many parts of the world.
This paper has highly influenced 14 other papers. However, the finding of effective gene transfer mechanisms within enterococci weakens these statements.
Enterococci at the crossroads of food safety?
A grouping of the strains on the basis of virulence traits, as well as case-by-case studies on overall phenotypic and genotypic characteristics, could enable us to trace pathogenicity schemes within the enterococcal population and better comprehend the microbial ecology of this heterogeneous group of bacteria. Resistance is acquired by gene transfer systems, such as conjugative or nonconjugative plasmids or transposons. Over the last two decades, enterococci have emerged crossroaes important hospital-acquired pathogens in immune-suppressed patients and intensive-care units.