Viral Infections, the Microbiome, and Probiotics.

Viral infections continue to cause considerable morbidity and mortality around the world. Recent rises in these infections are likely due to complex and multifactorial external drivers, including climate change, the increased mobility of people and goods and rapid demographic change to name but a few. In parallel with these external factors, we are gaining a better understanding of the internal factors associated with viral immunity.

Shaping the Future of Probiotics and Prebiotics.

Recent and ongoing developments in microbiome science are enabling new frontiers of research for probiotics and prebiotics. Novel types, mechanisms, and applications currently under study have the potential to change scientific understanding as well as nutritional and healthcare applications of these interventions. The expansion of related fields of microbiome-targeted interventions, and an evolving landscape for implementation across regulatory, policy, prescriber, and consumer spheres, portends an era of significant change.

Criteria to Qualify Microorganisms as "Probiotic" in Foods and Dietary Supplements.

Still relevant after 19 years, the FAO/WHO definition of probiotics can be translated into four simple and pragmatic criteria allowing one to conclude if specific strains of microorganisms qualify as a probiotic for use in foods and dietary supplements. Probiotic strains must be (i) sufficiently characterized; (ii) safe for the intended use; (iii) supported by at least one positive human clinical trial conducted according to generally accepted scientific standards or as per recommendations and provisions of local/national authorities when applicable; and (iv) alive in the product at an efficacious dose throughout shelf life. We provide clarity and detail how each of these four criteria can be assessed.

Antimicrobial susceptibility testing of lactic acid bacteria and bifidobacteria by broth microdilution method and Etest.

We applied two methods of broth microdilution and Etest for measuring minimal inhibition concentration (MIC) of lactic acid bacteria and bifidobacteria for 15 antimicrobial agents to compare the feasibility, reproducibility, and equivalence of the two methods. Both methods were originally described by the European projects PROSAFE and ACE-ART. In 84% combinations of strains and antimicrobial agents MIC differences between the two methods were within one Log(2) dilution.

Osmoregulation in Lactococcus lactis: BusR, a transcriptional repressor of the glycine betaine uptake system BusA.

The busA (opuA) locus of Lactococcus lactis encodes a glycine betaine uptake system. Transcription of busA is osmotically inducible and its induction after an osmotic stress is reduced in the presence of glycine betaine. Using a genetic screen in CLG802, an Escherichia coli strain carrying a lacZ transcriptional fusion expressed under the control of the busA promoter, we isolated a genomic fragment from the L.