Emerging probiotics: future therapeutics for human gut health

The microbial communities that colonize the human large intestine can influence many aspects of health and Bacillota strains, in particular, have been proposed as next-generation probiotics. Of note are strains including fibre-degraders, butyrate producers, lactate producers and utilizers, and other beneficial metabolic activities that are important for health. To illustrate the potential applications of colonic bacteria to design novel prebiotic formulations, a comparative genomics analysis of 16 bacterial strains isolated from the human gut was performed. This analysis revealed a high number of carbohydrate-active enzymes (CAZymes) in the genome sequences of understudied Lachnospiraceae and Oscillospiraceae members including Roseburia intestinalis L1-82, Roseburia faecis M72/1, Butyrivibrio fibrisolvens 16-4, and Ruminococcus bicirculans 80/3, ranging from 32 to 56 CAZymes across different strains. These strains showed complementary enzymatic profiles covering a wide range of different activities required to degrade prebiotic substrates derived from vegetable sources such as arabino- and xylo-oligosaccharides and pectic-oligosaccharides. These metabolic differences highlight the potential of these strains to cross feed and to allow the design novel probiotic consortia for microbiota-oriented interventions that could target specific disease conditions. These bacterial strains are, however, strict anaerobes and therefore special measures may need to be put in place to overcome these limitations.