Penny Young, ASAS/ASAP Intern
As we face the challenge of managing growing antibiotic resistance in pathogens, efforts to find antibiotic alternatives are redoubled.
An area that shows particular promise is the use of probiotics, both prophylactically and as a treatment measure. Research recently published in Translational Animal Science finds that yeast pro- and paraprobiotics are able to bind pathogenic bacteria that can cause disease in animals, such as Salmonella and Listeria species.
Other studies have found that probiotics and paraprobiotics have many modes of action. They can bind directly to pathogens, which helps to protect the animal by reducing the binding of pathogen to host intestinal cells and also facilitates removal of the pathogen from the host. The action of the yeast probiotics can take the form of a variety of mechanisms, with some involving direct antagonism or competitive inhibition that prevents colonization of the mucosal surface of the intestine. Some pathogenic bacteria produce toxins, and in some cases the yeast can protect the host by directly binding to these toxins. The yeast probiotics also may help to stimulate the host immune system, engaging a more effective response and thus improving outcomes.
The study investigated the nature of the interaction between two Saccharomyces cerevisiae probiotics and three S. cerevisiae paraprobiotics and 13 different pathogenic bacteria. The qualitative and quantitative nature of the binding was examined using scanning electron microscopy and filtration assays. The study also sought to determine the ability of Salmonella and Listeria to utilize yeast components as a carbon source.
The research team from Mississippi, led by Gabriel Posadas, found that the probiotics were more successful at adhering to the bacteria relative to the paraprobiotics. Out of the different bacterial species investigated, it was found that Escherichia coli and Listeria monocytogenes have the least binding potential to the pro and paraprobiotics. Interestingly, the study finds that the affinity for adherence differs between different species of the same genus, with Clostridium perfringens found to adhere to all the products tested, while C. difficile adhered better to probiotics than to paraprobiotics. There were also differences noted amongst the different subspecies of Salmonella enterica tested.
The study overall found that while yeast pro- and paraprobiotics show potential for use against bacteria due to their ability to bind bacteria, thus improving outcomes for the animal host, the interactions between the yeast treatments and bacteria have strain specific variations, hence administration of these yeast products as therapeutics needs to be specific against the particular pathogen in question.
To read the article in Translational Animal Science, click here.